Wound analysis device and method

ABSTRACT

Embodiments of tissue monitoring and therapy systems and methods are disclosed. In some embodiments, a monitoring and therapy system comprises collecting video images of a tissue site, amplifying said video images via Eulerian Video Magnification, and determining a treatment parameter from the amplified video images detectable by Eulerian Video Magnification. If the treatment parameter differs from a threshold, an alert may be generated.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a U.S. national stage application of InternationalPatent Application No. PCT/EP2018/062206, filed May 11, 2018, whichclaims the benefit of U.S. Provisional Application No. 62/506,551, filedMay 15, 2017; the disclosure of which is hereby incorporated byreference in its entirety.

BACKGROUND Technical Field

Embodiments described herein relate to apparatuses, systems, and methodsfor the treatment of wounds, for example monitoring wounds and providingan appropriate treatment.

Description of the Related Art

Modern wound treatment may involve multiple approaches including the useof various dressings, irrigants, debridement techniques, chemicals thatpromote healing, medicaments, and treatment negative pressure woundtherapy (NPWT). NPWT systems currently known in the art commonly involveplacing a cover that is impermeable or semi-permeable to fluids over thewound, using various means to seal the cover to the tissue of thepatient surrounding the wound, and connecting a source of negativepressure (such as a vacuum pump) to the cover in a manner so thatnegative pressure is created and maintained under the cover. Typically,wounds are monitoring by the naked eye and treatment is modified basedon the experience of the clinical practitioner.

However, prior art wound therapy provide little automated visualizationor information on the condition of a wound site or a tissue site,particularly early in the process before a wound has actually formed,for example during the early stages of pressure ulcer formation.Further, existing techniques for the evaluation of intact tissue andwounds are restricted by the limitations of the human eye or morerarely, standard videography techniques. Therefore, existing techniquesmay provide inadequate information about the state of tissue before awound exists; thus, improved methods and techniques forevaluating/detecting changes within wounds and tissue are needed.

Further, while nearly all areas of medicine may benefit from improvedinformation regarding the state of the tissue, organ, or system to betreated, particularly if such information is gathered in real-timeduring treatment, many types of treatments are still routinely performedwithout the use of sensor data collection. Instead, such treatments relyupon visual inspection by a caregiver or other limited means rather thanquantitative sensor data. For example, in the case of wound treatmentvia dressings and/or negative pressure wound therapy, data collection isgenerally limited to visual inspection by a caregiver and often theunderlying wounded tissue may be obscured by bandages or other visualimpediments. Even intact, unwounded skin may have underlying damage thatis not visible to the naked eye, such as a compromised vascular ordeeper tissue damage that may lead to an ulcer. Similar to woundtreatment, during orthopedic treatments requiring the immobilization ofa limb with a cast or other encasement, only limited information isgathered on the underlying tissue. In instances of internal tissuerepair, such as a bone plate, continued direct sensor-driven datacollection is not performed. Further, braces and/or sleeves used tosupport musculoskeletal function do not monitor the functions of theunderlying muscles or the movement of the limbs. Outside of directtreatments, common hospital room items such as beds and blankets couldbe improved by adding capability to monitor patient parameters.

Therefore, there is a need for improved sensor monitoring, particularlythrough the use of sensor-enabled substrates which can be incorporatedinto existing treatment regimes.

SUMMARY

Certain disclosed embodiments relate to devices, methods, and systemsfor monitoring tissues. It will be understood by one of skill of artthat application of the devices, methods, and systems described hereinare not limited to a particular tissue or a particular injury.

In certain embodiments, a treatment system may comprise a visualizationsensor configured to be positioned over a tissue site, the visualizationsensor configured to collect video data of the tissue site, an outputconfigured to provide an alert, and a controller in communication withboth the visualization sensor and the output, the controller configuredto: amplify the video data by Eulerian video magnification, determine atreatment parameter from the amplified video data and cause the outputto provide an alert in response to determining that the treatmentparameter differs from a threshold.

In some embodiments, the threshold corresponds to a probability ofoccurrence of a pressure injury. The controller may be contained withina smartphone. The visualization sensor may be configured to communicatewirelessly with the controller. The controller may be configured tocommunicate wirelessly with the output. The controller can be configuredto compare the treatment parameter to a plurality of thresholds. Thevisualization sensor may comprise an RGB detector. The alert maycomprise an audible alarm and/or a visual alarm.

The controller may be configured to determine the tissue parameter bycalculating the change in a red value between two or more frames ofvideo data.

In certain embodiments, a system for identifying incision sites maycomprise: a visualization sensor configured to be positioned over atissue site, the visualization sensor configured to collect video dataof the tissue site, a controller in communication with the visualizationsensor, the controller configured to: amplify the video data by Eulerianvideo magnification, identify Langer Lines in the tissue site from theamplified video data, map the Langer Lines over the video data of thetissue site; and display the Langer Lines on a display.

The system may further comprise an output configured to provide anincision site alert. The incision site alert may comprise an orientationand a position.

In certain embodiments, a system for monitoring the treatment of atissue site, may comprise: an ultrasound generator, the ultrasoundgenerator configured to deliver therapeutic ultrasound to an internaltissue site, and a visualization sensor configured to be positioned overthe internal tissue site, the visualization sensor configured to collectmagnetic induction tomography video data of the tissue site. The systemmay comprise an output configured to provide an alert when the magneticinduction tomography video data exceeds a threshold.

In some embodiments, a method of operating a treatment system comprisinga visualization sensor and a controller may comprise: by thevisualization sensor positioned over a tissue site, collecting videodata of the tissue site, and by the controller: amplifying the videodata by Eulerian video magnification, determining a treatment parameterfrom the amplified video data, and causing provision of an alert inresponse to determining that the treatment parameter differs from athreshold.

In some embodiments, a method of operating a treatment system comprisinga visualization sensor and a controller may comprise: by thevisualization sensor positioned over a tissue site, collecting videodata of the tissue site, and by the controller: amplifying the videodata by Eulerian video magnification, determining a red-delta value fromthe amplified video data; and causing a provision of an alert if thered-delta value indicates the presence of a blood vessel in the tissuesite.

Other embodiments are described below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a reduced pressure wound therapy system according tosome embodiments.

FIGS. 2A, 2B, and 2C illustrate a pump assembly and canister accordingto some embodiments.

FIG. 3 illustrates an embodiment of a process for video amplificationknown as Eulerian Video Magnification.

FIG. 4 illustrates an embodiment of a wound monitoring and treatmentsystem.

FIG. 5A illustrates embodiment of a wound monitoring and treatmentsystem.

FIG. 5B illustrates an embodiment of a sampling method for samplingframes from a video.

FIG. 6 illustrates an embodiment of a wound diagnostic system.

FIG. 7 illustrates an embodiment of a method and/or system for mappingLanger's Lines and identifying an incision site.

FIG. 8 illustrates an embodiment of a system for monitoring thetreatment of a tissue site with ultrasound via magnetic inductiontomography.

DETAILED DESCRIPTION

Embodiments disclosed herein relate to apparatuses and methods ofmonitoring and treating biological tissue with sensor-enabledsubstrates. The embodiments disclosed herein are not limited totreatment or monitoring of a particular type of tissue or injury,instead the sensor-enabled technologies disclosed herein are broadlyapplicable to any type of therapy that may benefit from sensor-enabledsubstrates. Some implementations utilize sensors and data collectionrelied upon by health care providers to make both diagnostic and patientmanagement decisions.

Some embodiments disclosed herein relate to the use of sensors mountedon or embedded within substrates configured to be used in the treatmentof both intact and damaged human or animal tissue. Such sensors maycollect information about the surrounding tissue and transmit suchinformation to a computing device or a caregiver to be utilized infurther treatment. In certain embodiments, such sensors may be attachedto the skin anywhere on the body, including areas for monitoringarthritis, temperature, or other areas that may be prone to problems andrequire monitoring. Sensors disclosed herein may also incorporatemarkers, such as radiopaque markers, to indicate the presence of thedevice, for example prior to performing an MRI or other technique.

The sensor embodiments disclosed herein may be used in combination withclothing. Non-limiting examples of clothing for use with embodiments ofthe sensors disclosed herein include shirts, pants, trousers, dresses,undergarments, outer-garments, gloves, shoes, hats, and other suitablegarments. In certain embodiments, the sensor embodiments disclosedherein may be welded into or laminated into/onto the particulargarments. The sensor embodiments may be printed directly onto thegarment and/or embedded into the fabric. Breathable and printablematerials such as microporous membranes may also be suitable.

Sensor embodiments disclosed herein may be incorporated into cushioningor bed padding, such as within a hospital bed, to monitor patientcharacteristics, such as any characteristic disclosed herein. In certainembodiments, a disposable film containing such sensors could be placedover the hospital bedding and removed/replaced as needed.

In some implementations, the sensor embodiments disclosed herein mayincorporate energy harvesting, such that the sensor embodiments areself-sustaining. For example, energy may be harvested from thermalenergy sources, kinetic energy sources, chemical gradients, or anysuitable energy source.

The sensor embodiments disclosed herein may be utilized inrehabilitation devices and treatments, including sports medicine. Forexample, the sensor embodiments disclosed herein may be used in braces,sleeves, wraps, supports, and other suitable items. Similarly, thesensor embodiments disclosed herein may be incorporated into sportingequipment, such as helmets, sleeves, and/or pads. For example, suchsensor embodiments may be incorporated into a protective helmet tomonitor characteristics such as acceleration, which may be useful inconcussion diagnosis.

The sensor embodiments disclosed herein may be used in coordination withsurgical devices, for example, the NAVIO surgical system by Smith &Nephew Inc. In implementations, the sensor embodiments disclosed hereinmay be in communication with such surgical devices to guide placement ofthe surgical devices. In some implementations, the sensor embodimentsdisclosed herein may monitor blood flow to or away from the potentialsurgical site or ensure that there is no blood flow to a surgical site.Further surgical data may be collected to aid in the prevention ofscarring and monitor areas away from the impacted area.

To further aid in surgical techniques, the sensors disclosed herein maybe incorporated into a surgical drape to provide information regardingtissue under the drape that may not be immediately visible to the nakedeye. For example, a sensor embedded flexible drape may have sensorspositioned advantageously to provide improved area-focused datacollection. In certain implementations, the sensor embodiments disclosedherein may be incorporated into the border or interior of a drape tocreate fencing to limit/control the surgical theater.

Sensor embodiments as disclosed herein may also be utilized forpre-surgical assessment. For example, such sensor embodiments may beused to collect information about a potential surgical site, such as bymonitoring skin and the underlying tissues for a possible incision site.For example, perfusion levels or other suitable characteristics may bemonitored at the surface of the skin and deeper in the tissue to assesswhether an individual patient may be at risk for surgical complications.Sensor embodiments such as those disclosed herein may be used toevaluate the presence of microbial infection and provide an indicationfor the use of antimicrobials. Further, sensor embodiments disclosedherein may collect further information in deeper tissue, such asidentifying pressure ulcer damage and/or the fatty tissue levels.

The sensor embodiments disclosed herein may be utilized incardiovascular monitoring. For example, such sensor embodiments may beincorporated into a flexible cardiovascular monitor that may be placedagainst the skin to monitor characteristics of the cardiovascular systemand communicate such information to another device and/or a caregiver.For example, such a device may monitor pulse rate, oxygenation of theblood, and/or electrical activity of the heart. Similarly, the sensorembodiments disclosed herein may be utilized for neurophysiologicalapplications, such as monitoring electrical activity of neurons.

The sensor embodiments disclosed herein may be incorporated intoimplantable devices, such as implantable orthopedic implants, includingflexible implants. Such sensor embodiments may be configured to collectinformation regarding the implant site and transmit this information toan external source. In some embodiments, an internal source may alsoprovide power for such an implant.

The sensor embodiments disclosed herein may also be utilized formonitoring biochemical activity on the surface of the skin or below thesurface of the skin, such as lactose buildup in muscle or sweatproduction on the surface of the skin. In some embodiments, othercharacteristics may be monitored, such as glucose concentration, urineconcentration, tissue pressure, skin temperature, skin surfaceconductivity, skin surface resistivity, skin hydration, skin maceration,and/or skin ripping.

Sensor embodiments as disclosed herein may be incorporated into Ear,Nose, and Throat (ENT) applications. For example, such sensorembodiments may be utilized to monitor recovery from ENT-relatedsurgery, such as wound monitoring within the sinus passage.

As described in greater detail below, the sensor embodiments disclosedherein may encompass sensor printing technology with encapsulation, suchas encapsulation with a polymer film Such a film may be constructedusing any polymer described herein, such as polyurethane. Encapsulationof the sensor embodiments may provide waterproofing of the electronicsand protection from local tissue, local fluids, and other sources ofpotential damage.

In certain embodiments, the sensors disclosed herein may be incorporatedinto an organ protection layer such as disclosed below. Such asensor-embedded organ protection layer may both protect the organ ofinterest and confirm that the organ protection layer is in position andproviding protection. Further, a sensor-embedded organ protection layermay be utilized to monitor the underlying organ, such as by monitoringblood flow, oxygenation, and other suitable markers of organ health. Insome embodiments, a sensor-enabled organ protection layer may be used tomonitor a transplanted organ, such as by monitoring the fat and musclecontent of the organ. Further, sensor-enabled organ protection layersmay be used to monitor an organ during and after transplant, such asduring rehabilitation of the organ.

The sensor embodiments disclosed herein may be incorporated intotreatments for wounds (disclosed in greater detail below) or in avariety of other applications. Non-limiting examples of additionalapplications for the sensor embodiments disclosed herein include:monitoring and treatment of intact skin, cardiovascular applicationssuch as monitoring blood flow, orthopedic applications such asmonitoring limb movement and bone repair, neurophysiologicalapplications such as monitoring electrical impulses, and any othertissue, organ, system, or condition that may benefit from improvedsensor-enabled monitoring.

Wound Therapy

Some embodiments disclosed herein relate to wound therapy for a human oranimal body. Therefore, any reference to a wound herein can refer to awound on a human or animal body, and any reference to a body herein canrefer to a human or animal body. The disclosed technology embodimentsmay relate to preventing or minimizing damage to physiological tissue orliving tissue, or to the treatment of damaged tissue (for example, awound as described herein) wound with or without reduced pressure,including for example a source of negative pressure and wound dressingcomponents and apparatuses. The apparatuses and components comprisingthe wound overlay and packing materials or internal layers, if any, aresometimes collectively referred to herein as dressings. In someembodiments, the wound dressing can be provided to be utilized withoutreduced pressure.

Some embodiments disclosed herein relate to wound therapy for a human oranimal body. Therefore, any reference to a wound herein can refer to awound on a human or animal body, and any reference to a body herein canrefer to a human or animal body. The disclosed technology embodimentsmay relate to preventing or minimizing damage to physiological tissue orliving tissue, or to the treatment of damaged tissue (for example, awound as described herein).

As used herein the expression “wound” may include an injury to livingtissue may be caused by a cut, blow, or other impact, typically one inwhich the skin is cut or broken. A wound may be a chronic or acuteinjury. Acute wounds occur as a result of surgery or trauma. They movethrough the stages of healing within a predicted timeframe. Chronicwounds typically begin as acute wounds. The acute wound can become achronic wound when it does not follow the healing stages resulting in alengthened recovery. It is believed that the transition from acute tochronic wound can be due to a patient being immuno-compromised.

Chronic wounds may include for example: venous ulcers (such as thosethat occur in the legs), which account for the majority of chronicwounds and mostly affect the elderly, diabetic ulcers (for example, footor ankle ulcers), peripheral arterial disease, pressure ulcers, orepidermolysis bullosa (EB).

Examples of other wounds include, but are not limited to, abdominalwounds or other large or incisional wounds, either as a result ofsurgery, trauma, sterniotomies, fasciotomies, or other conditions,dehisced wounds, acute wounds, chronic wounds, subacute and dehiscedwounds, traumatic wounds, flaps and skin grafts, lacerations, abrasions,contusions, burns, diabetic ulcers, pressure ulcers, stoma, surgicalwounds, trauma and venous ulcers or the like.

Wounds may also include a deep tissue injury. Deep tissue injury is aterm proposed by the National Pressure Ulcer Advisory Panel (NPUAP) todescribe a unique form of pressure ulcers. These ulcers have beendescribed by clinicians for many years with terms such as purplepressure ulcers, ulcers that are likely to deteriorate and bruises onbony prominences.

Wound may also include tissue at risk of becoming a wound as discussedherein. For example, tissue at risk may include tissue over a bonyprotuberance (at risk of deep tissue injury/insult) or pre-surgicaltissue (for example, knee tissue) that may has the potential to be cut(for example, for joint replacement/surgical alteration/reconstruction).

Some embodiments relate to methods of treating a wound with thetechnology disclosed herein in conjunction with one or more of thefollowing: advanced footwear, turning a patient, offloading (such as,offloading diabetic foot ulcers), treatment of infection, systemix,antimicrobial, antibiotics, surgery, removal of tissue, affecting bloodflow, physiotherapy, exercise, bathing, nutrition, hydration, nervestimulation, ultrasound, electrostimulation, oxygen therapy, microwavetherapy, active agents ozone, antibiotics, antimicrobials, or the like.

Alternatively or additionally, a wound may be treated using topicalnegative pressure and/or traditional advanced wound care, which is notaided by the using of applied negative pressure (may also be referred toas non-negative pressure therapy).

Advanced wound care may include use of an absorbent dressing, anocclusive dressing, use of an antimicrobial and/or debriding agents in awound dressing or adjunct, a pad (for example, a cushioning orcompressive therapy, such as stockings or bandages), or the like.

In some embodiments, treatment of such wounds can be performed usingtraditional wound care, wherein a dressing can be applied to the woundto facilitate and promote healing of the wound.

Some embodiments relate to methods of manufacturing a wound dressingcomprising providing a wound dressing as disclosed herein.

The wound dressings that may be utilized in conjunction with thedisclosed technology include any known dressing in the art. Thetechnology is applicable to negative pressure therapy treatment as wellas non-negative pressure therapy treatment.

In some embodiments, a wound dressing comprises one or more absorbentlayer(s). The absorbent layer may be a foam or a superabsorbent.

In some embodiments, wound dressings may comprise a dressing layerincluding a polysaccharide or modified polysaccharide, apolyvinylpyrrolidone, a polyvinyl alcohol, a polyvinyl ether, apolyurethane, a polyacrylate, a polyacrylamide, collagen, or gelatin ormixtures thereof. Dressing layers comprising the polymers listed areknown in the art as being useful for forming a wound dressing layer foreither negative pressure therapy or non-negative pressure therapy.

In some embodiments, the polymer matrix may be a polysaccharide ormodified polysaccharide.

In some embodiments, the polymer matrix may be a cellulose. Cellulosematerial may include hydrophilically modified cellulose such as methylcellulose, carboxymethyl cellulose (CMC), carboxymethyl cellulose (CEC),ethyl cellulose, propyl cellulose, hydroxyethyl cellulose, hydroxypropylcellulose, hydroxypropylmethyl cellulose, carboxyethyl sulphonatecellulose, cellulose alkyl sulphonate, or mixtures thereof.

In certain embodiments, cellulose material may be cellulose alkylsulphonate. The alkyl moiety of the alkyl sulphonate substituent groupmay have an alkyl group having 1 to 6 carbon atoms, such as methyl,ethyl, propyl, or butyl. The alkyl moiety may be branched or unbranched,and hence suitable propyl sulphonate substituents may be 1- or2-methyl-ethylsulphonate. Butyl sulphonate substituents may be2-ethyl-ethylsulphonate, 2,2-dimethyl-ethylsulphonate, or1,2-dimethyl-ethylsulphonate. The alkyl sulphonate substituent group maybe ethyl sulphonate. The cellulose alkyl sulphonate is described inWO10061225, US2016/114074, US2006/0142560, or U.S. Pat. No. 5,703,225,the disclosures of which are hereby incorporated by reference in theirentirety.

Cellulose alkyl sulfonates may have varying degrees of substitution, thechain length of the cellulose backbone structure, and the structure ofthe alkyl sulfonate substituent. Solubility and absorbency are largelydependent on the degree of substitution: as the degree of substitutionis increased, the cellulose alkyl sulfonate becomes increasinglysoluble. It follows that, as solubility increases, absorbency increases.

In some embodiments, a wound dressing also comprises a top or coverlayer.

The thickness of the wound dressing disclosed herein may be between 1 to20, or 2 to 10, or 3 to 7 mm.

In some embodiments, the disclosed technology may be used in conjunctionwith a non-negative pressure dressing. A non-negative pressure wounddressing suitable for providing protection at a wound site may comprise:

-   -   an absorbent layer for absorbing wound exudate and    -   an obscuring element for at least partially obscuring a view of        wound exudate absorbed by the absorbent layer in use.

The obscuring element may be partially translucent.

The obscuring element may be a masking layer.

The non-negative pressure wound dressing may further comprise a regionin or adjacent the obscuring element for allowing viewing of theabsorbent layer. For example, the obscuring element layer may beprovided over a central region of the absorbent layer and not over aborder region of the absorbent layer. In some embodiments, the obscuringelement is of hydrophilic material or is coated with a hydrophilicmaterial.

The obscuring element may comprise a three-dimensional knitted spacerfabric. The spacer fabric is known in the art and may include a knittedspacer fabric layer.

The obscuring element may further comprise an indicator for indicatingthe need to change the dressing.

In some embodiments, the obscuring element is provided as a layer atleast partially over the absorbent layer, further from a wound site thanthe absorbent layer in use.

The non-negative pressure wound dressing may further comprise aplurality of openings in the obscuring element for allowing fluid tomove therethrough. The obscuring element may comprise, or may be coatedwith, a material having size-exclusion properties for selectivelypermitting or preventing passage of molecules of a predetermined size orweight.

The obscuring element may be configured to at least partially mask lightradiation having wavelength of 600 nm and less.

The obscuring element may be configured to reduce light absorption by50% or more.

The obscuring element may be configured to yield a CIE L* value of 50 ormore, and optionally 70 or more. In some embodiments, the obscuringelement may be configured to yield a CIE L* value of 70 or more.

In some embodiments, the non-negative pressure wound dressing mayfurther comprise at least one of a wound contact layer, a foam layer, anodor control element, a pressure-resistant layer and a cover layer.

In some embodiments, the cover layer is present, and the cover layer isa translucent film Typically, the translucent film has a moisture vapourpermeability of 500 g/m2/24 hours or more.

The translucent film may be a bacterial bather.

In some embodiments, the non-negative pressure wound dressing asdisclosed herein comprises the wound contact layer and the absorbentlayer overlies the wound contact layer. The wound contact layer carriesan adhesive portion for forming a substantially fluid tight seal overthe wound site.

The non-negative pressure wound dressing as disclosed herein maycomprise the obscuring element and the absorbent layer being provided asa single layer.

In some embodiments, the non-negative pressure wound dressing disclosedherein comprises the foam layer, and the obscuring element is of amaterial comprising components that may be displaced or broken bymovement of the obscuring element.

In some embodiments, the non-negative pressure wound dressing comprisesan odor control element, and in another embodiment the dressing does notinclude an odor control element. When present, the odor control elementmay be dispersed within or adjacent the absorbent layer or the obscuringelement. Alternatively, when present the odor control element may beprovided as a layer sandwiched between the foam layer and the absorbentlayer.

In some embodiments, the disclosed technology for a non-negativepressure wound dressing comprises a method of manufacturing a wounddressing, comprising: providing an absorbent layer for absorbing woundexudate; and providing an obscuring element for at least partiallyobscuring a view of wound exudate absorbed by the absorbent layer inuse.

In some embodiments, the non-negative pressure wound dressing is may besuitable for providing protection at a wound site, comprising: anabsorbent layer for absorbing wound exudate; and a shielding layerprovided over the absorbent layer, and further from a wound-facing sideof the wound dressing than the absorbent layer. The shielding layer maybe provided directly over the absorbent layer. In some embodiments, theshielding layer comprises a three-dimensional spacer fabric layer.

The shielding layer increases the area over which a pressure applied tothe dressing is transferred by 25% or more or the initial area ofapplication. For example the shielding layer increases the area overwhich a pressure applied to the dressing is transferred by 50% or more,and optionally by 100% or more, and optionally by 200% or more.

The shielding layer may comprise 2 or more sub-layers, wherein a firstsub-layer comprises through holes and a further sub-layer comprisesthrough holes and the through holes of the first sub-layer are offsetfrom the through holes of the further sub-layer.

The non-negative pressure wound dressing as disclosed herein may furthercomprise a permeable cover layer for allowing the transmission of gasand vapour therethrough, the cover layer provided over the shieldinglayer, wherein through holes of the cover layer are offset from throughholes of the shielding layer.

The non-negative pressure wound dressing may be suitable for treatmentof pressure ulcers.

A more detailed description of the non-negative pressure dressingdisclosed hereinabove is provided in WO2013007973, the entirety of whichis hereby incorporated by reference.

In some embodiments, the non-negative pressure wound dressing may be amulti-layered wound dressing comprising: a fibrous absorbent layer forabsorbing exudate from a wound site; and a support layer configured toreduce shrinkage of at least a portion of the wound dressing.

In some embodiments, the multi-layered wound dressing disclosed herein,further comprises a liquid impermeable film layer, wherein the supportlayer is located between the absorbent layer and the film layer.

The support layer disclosed herein may comprise a net. The net maycomprise a geometric structure having a plurality of substantiallygeometric apertures extending therethrough. The geometric structure mayfor example comprise a plurality of bosses substantially evenly spacedand joined by polymer strands to form the substantially geometricapertures between the polymer strands.

The net may be formed from high density polyethylene.

The apertures may have an area from 0.005 to 0.32 mm2.

The support layer may have a tensile strength from 0.05 to 0.06 Nm.

The support layer may have a thickness of from 50 to 150 μm.

In some embodiments, the support layer is located directly adjacent theabsorbent layer. Typically, the support layer is bonded to fibers in atop surface of the absorbent layer. The support layer may furthercomprise a bonding layer, wherein the support layer is heat laminated tothe fibers in the absorbent layer via the bonding layer. The bondinglayer may comprise a low melting point adhesive such as ethylene-vinylacetate adhesive.

In some embodiments, the multi-layered wound dressing disclosed hereinfurther comprises an adhesive layer attaching the film layer to thesupport layer.

In some embodiments, the multi-layered wound dressing disclosed hereinfurther comprises a wound contact layer located adjacent the absorbentlayer for positioning adjacent a wound. The multi-layered wound dressingmay further comprise a fluid transport layer between the wound contactlayer and the absorbent layer for transporting exudate away from a woundinto the absorbent layer.

A more detailed description of the multi-layered wound dressingdisclosed hereinabove is provided in GB patent application filed on 28Oct. 2016 with application number GB1618298.2, the entirety of which ishereby incorporated by reference.

In some embodiments, the disclosed technology may be incorporated in awound dressing comprising a vertically lapped material comprising: afirst layer of an absorbing layer of material, and a second layer ofmaterial, wherein the first layer being constructed from at least onelayer of non-woven textile fibers, the non-woven textile fibers beingfolded into a plurality of folds to form a pleated structure. In someembodiments, the wound dressing further comprises a second layer ofmaterial that is temporarily or permanently connected to the first layerof material.

Typically the vertically lapped material has been slitted.

In some embodiments, the first layer has a pleated structure having adepth determined by the depth of pleats or by the slitting width. Thefirst layer of material may be a moldable, lightweight, fiber-basedmaterial, blend of material or composition layer.

The first layer of material may comprise one or more of manufacturedfibers from synthetic, natural or inorganic polymers, natural fibers ofa cellulosic, proteinaceous or mineral source.

The wound dressing may comprise two or more layers of the absorbinglayer of material vertically lapped material stacked one on top of theother, wherein the two or more layers have the same or differentdensities or composition.

The wound dressing may in some embodiments comprise only one layer ofthe absorbing layer of material vertically lapped material.

The absorbing layer of material is a blend of natural or synthetic,organic or inorganic fibers, and binder fibers, or bicomponent fiberstypically PET with a low melt temperature PET coating to soften atspecified temperatures and to act as a bonding agent in the overallblend.

In some embodiments, the absorbing layer of material may be a blend of 5to 95% thermoplastic polymer, and 5 to 95 wt % of a cellulose orderivative thereof.

In some embodiments, the wound dressing disclosed herein has a secondlayer comprises a foam or a dressing fixative.

The foam may be a polyurethane foam. The polyurethane foam may have anopen or closed pore structure.

The dressing fixative may include bandages, tape, gauze, or backinglayer.

In some embodiments, the wound dressing as disclosed herein comprisesthe absorbing layer of material connected directly to a second layer bylamination or by an adhesive, and the second layer is connected to adressing fixative layer. The adhesive may be an acrylic adhesive, or asilicone adhesive.

In some embodiments, the wound dressing as disclosed herein furthercomprises layer of a superabsorbent fiber, or a viscose fiber or apolyester fiber.

In some embodiments, the wound dressing as disclosed herein furthercomprises a backing layer. The backing layer may be a transparent oropaque film. Typically the backing layer comprises a polyurethane film(typically a transparent polyurethane film).

A more detailed description of the multi-layered wound dressingdisclosed hereinabove is provided in GB patent applications filed on 12Dec. 2016 with application number GB1621057.7; and 22 Jun. 2017 withapplication number GB1709987.0, the entirety of each of which is herebyincorporated by reference.

In some embodiments, the non-negative pressure wound dressing maycomprise an absorbent component for a wound dressing, the componentcomprising a wound contacting layer comprising gel forming fibers boundto a foam layer, wherein the foam layer is bound directly to the woundcontact layer by an adhesive, polymer based melt layer, by flamelamination or by ultrasound.

The absorbent component may be in a sheet form.

The wound contacting layer may comprise a layer of woven or non-woven orknitted gel forming fibers.

The foam layer may be an open cell foam, or closed cell foam, typicallyan open cell foam. The foam layer is a hydrophilic foam.

The wound dressing may comprise the component that forms an island indirect contact with the wound surrounded by periphery of adhesive thatadheres the dressing to the wound. The adhesive may be a silicone oracrylic adhesive, typically a silicone adhesive.

The wound dressing may be covered by a film layer on the surface of thedressing furthest from the wound.

A more detailed description of the wound dressing of this typehereinabove is provided in EP2498829, the entirety of which is herebyincorporated by reference.

In some embodiments, the non-negative pressure wound dressing maycomprise a multi layered wound dressing for use on wounds producing highlevels of exudate, characterized in that the dressing comprising: atransmission layer having an MVTR of at least 300 μm2/24 hours, anabsorbent core comprising gel forming fibers capable of absorbing andretaining exudate, a wound contacting layer comprising gel formingfibers which transmits exudate to the absorbent core and a keying layerpositioned on the absorbent core, the absorbent core and woundcontacting layer limiting the lateral spread of exudate in the dressingto the region of the wound.

The wound dressing may be capable of handling at least 6 g (or 8 g and15 g) of fluid per 10 cm2 of dressing in 24 hours.

The wound dressing may comprise gel forming fibers that are chemicallymodified cellulosic fibers in the form of a fabric. The fibers mayinclude carboxymethylated cellulose fibers, typically sodiumcarboxymethylcellulose fiber.

The wound dressing may comprise a wound contact layer with a lateralwicking rate from 5 mm per minute to 40 mm per minute. The wound contactlayer may have a fiber density between 25 gm2 and 55 gm2, such as 35gm2.

The absorbent core may have an absorbency of exudate of at least 10 g/g,and typically a rate of lateral wicking of less the 20 mm per minute.

The absorbent core may have a blend in the range of up to 25% cellulosicfibers by weight and 75% to 100% gel forming fibers by weight.

Alternatively, the absorbent core may have a blend in the range of up to50% cellulosic fibers by weight and 50% to 100% gel forming fibers byweight. For example the blend is in the range of 50% cellulosic fibersby weight and 50% gel forming fibers by weight.

The fiber density in the absorbent core may be between 150 gm2 and 250gm2, or about 200 gm2.

The wound dressing when wet may have shrinkage that is less than 25% orless than 15% of its original size/dimension.

The wound dressing may comprise a transmission layer and the layer is afoam. The transmission layer may be a polyurethane foam laminated to apolyurethane film.

The wound dressing may comprise one or more layers selected from thegroup comprising a soluble medicated film layer; an odor-absorbinglayer; a spreading layer and an additional adhesive layer.

The wound dressing may be 2 mm and 4 mm thick.

The wound dressing may be characterized in that the keying layer bondsthe absorbent core to a neighboring layer. In some embodiments, thekeying layer may be positioned on either the wound facing side of theabsorbent core or the non-wound facing side of the absorbent core. Insome embodiments, the keying layer is positioned between the absorbentcore and the wound contact layer. The keying layer is a polyamide web.

A more detailed description of the wound dressing of this typehereinabove is provided in EP1718257, the entirety of which is herebyincorporated by reference.

In some embodiments, the non-negative pressure wound dressing may be acompression bandage. Compression bandages are known for use in thetreatment of oedema and other venous and lymphatic disorders, e.g., ofthe lower limbs.

A compression bandage systems typically employ multiple layers includinga padding layer between the skin and the compression layer or layers.The compression bandage may be useful for wounds such as handling venousleg ulcers.

The compression bandage in some embodiments may comprise a bandagesystem comprising an inner skin facing layer and an elastic outer layer,the inner layer comprising a first ply of foam and a second ply of anabsorbent nonwoven web, the inner layer and outer layer beingsufficiently elongated so as to be capable of being wound about apatient's limb. A compression bandage of this type is disclosed inWO99/58090, the entirety of which is hereby incorporated by reference.

In some embodiments, the compression bandage system comprises: a) aninner skin facing, elongated, elastic bandage comprising: (i) anelongated, elastic substrate, and

(ii) an elongated layer of foam, said foam layer being affixed to a faceof said substrate and extending 33% or more across said face ofsubstrate in transverse direction and 67% or more across said face ofsubstrate in longitudinal direction; and b) an outer, elongated,self-adhering elastic bandage; said bandage having a compressive forcewhen extended; wherein, in use, said foam layer of the inner bandagefaces the skin and the outer bandage overlies the inner bandage. Acompression bandage of this type is disclosed in WO2006/110527, theentirety of which is hereby incorporated by reference.

In some embodiments other compression bandage systems such as thosedisclosed in U.S. Pat. No. 6,759,566 and US 2002/0099318, the entiretyof each of which is hereby incorporated by reference.

Negative Pressure Wound Dressing

In some embodiments, treatment of such wounds can be performed usingnegative pressure wound therapy, wherein a reduced or negative pressurecan be applied to the wound to facilitate and promote healing of thewound. It will also be appreciated that the wound dressing and methodsas disclosed herein may be applied to other parts of the body, and arenot necessarily limited to treatment of wounds.

It will be understood that embodiments of the present disclosure aregenerally applicable to use in topical negative pressure (“TNP”) therapysystems. Briefly, negative pressure wound therapy assists in the closureand healing of many forms of “hard to heal” wounds by reducing tissueoedema; encouraging blood flow and granular tissue formation; removingexcess exudate and may reduce bacterial load (and thus infection risk).In addition, the therapy allows for less disturbance of a wound leadingto more rapid healing. TNP therapy systems may also assist on thehealing of surgically closed wounds by removing fluid and by helping tostabilize the tissue in the apposed position of closure. A furtherbeneficial use of TNP therapy can be found in grafts and flaps whereremoval of excess fluid is important and close proximity of the graft totissue is required in order to ensure tissue viability.

Negative pressure therapy can be used for the treatment of open orchronic wounds that are too large to spontaneously close or otherwisefail to heal by means of applying negative pressure to the site of thewound. Topical negative pressure (TNP) therapy or negative pressurewound therapy (NPWT) involves placing a cover that is impermeable orsemi-permeable to fluids over the wound, using various means to seal thecover to the tissue of the patient surrounding the wound, and connectinga source of negative pressure (such as a vacuum pump) to the cover in amanner so that negative pressure is created and maintained under thecover. It is believed that such negative pressures promote wound healingby facilitating the formation of granulation tissue at the wound siteand assisting the body's normal inflammatory process whilesimultaneously removing excess fluid, which may contain adversecytokines or bacteria.

Some of the dressings used in NPWT can include many different types ofmaterials and layers, for example, gauze, pads, foam pads or multi-layerwound dressings. One example of a multi-layer wound dressing is the PICOdressing, available from Smith & Nephew, includes a wound contact layerand a superabsorbent layer beneath a backing layer to provide acanister-less system for treating a wound with NPWT. The wound dressingmay be sealed to a suction port providing connection to a length oftubing, which may be used to pump fluid out of the dressing or totransmit negative pressure from a pump to the wound dressing.Additionally, RENASYS-F, RENASYS-G, RENASYS-AB, and RENASYS-F/AB,available from Smith & Nephew, are additional examples of NPWT wounddressings and systems. Another example of a multi-layer wound dressingis the ALLEVYN Life dressing, available from Smith & Nephew, whichincludes a moist wound environment dressing that is used to treat thewound without the use of negative pressure.

As is used herein, reduced or negative pressure levels, such as −X mmHg,represent pressure levels relative to normal ambient atmosphericpressure, which can correspond to 760 mmHg (or 1 atm, 29.93 inHg,101.325 kPa, 14.696 psi, etc.). Accordingly, a negative pressure valueof −X mmHg reflects absolute pressure that is X mmHg below 760 mmHg or,in other words, an absolute pressure of (760−X) mmHg In addition,negative pressure that is “less” or “smaller” than X mmHg corresponds topressure that is closer to atmospheric pressure (such as, −40 mmHg isless than −60 mmHg). Negative pressure that is “more” or “greater” than−X mmHg corresponds to pressure that is further from atmosphericpressure (such as, −80 mmHg is more than −60 mmHg). In some embodiments,local ambient atmospheric pressure is used as a reference point, andsuch local atmospheric pressure may not necessarily be, for example, 760mmHg.

The negative pressure range for some embodiments of the presentdisclosure can be approximately −80 mmHg, or between about −20 mmHg and−200 mmHg Note that these pressures are relative to normal ambientatmospheric pressure, which can be 760 mmHg Thus, −200 mmHg would beabout 560 mmHg in practical terms. In some embodiments, the pressurerange can be between about −40 mmHg and −150 mmHg. Alternatively apressure range of up to −75 mmHg, up to −80 mmHg or over −80 mmHg can beused. Also in other embodiments a pressure range of below −75 mmHg canbe used. Alternatively, a pressure range of over approximately −100mmHg, or even −150 mmHg, can be supplied by the negative pressureapparatus.

In some embodiments of wound closure devices described herein, increasedwound contraction can lead to increased tissue expansion in thesurrounding wound tissue. This effect may be increased by varying theforce applied to the tissue, for example by varying the negativepressure applied to the wound over time, possibly in conjunction withincreased tensile forces applied to the wound via embodiments of thewound closure devices. In some embodiments, negative pressure may bevaried over time for example using a sinusoidal wave, square wave, or insynchronization with one or more patient physiological indices (such as,heartbeat). Examples of such applications where additional disclosurerelating to the preceding may be found include U.S. Pat. No. 8,235,955,titled “Wound treatment apparatus and method,” issued on Aug. 7, 2012;and U.S. Pat. No. 7,753,894, titled “Wound cleansing apparatus withstress,” issued Jul. 13, 2010. The disclosures of both of these patentsare hereby incorporated by reference in their entirety.

Embodiments of the wound dressings, wound dressing components, woundtreatment apparatuses and methods described herein may also be used incombination or in addition to those described in InternationalApplication No. PCT/IB2013/001469, filed May 22, 2013, published as WO2013/175306 A2 on Nov. 28, 2013, titled “APPARATUSES AND METHODS FORNEGATIVE PRESSURE WOUND THERAPY,” U.S. patent application Ser. No.14/418,908, filed Jan. 30, 2015, published as US 2015/0190286 A1 on Jul.9, 2015, titled “WOUND DRESSING AND METHOD OF TREATMENT,” thedisclosures of which are hereby incorporated by reference in theirentireties. Embodiments of the wound dressings, wound dressingcomponents, wound treatment apparatuses and methods described herein mayalso be used in combination or in addition to those described in U.S.patent application Ser. No. 13/092,042, filed Apr. 21, 2011, publishedas US2011/0282309, titled “WOUND DRESSING AND METHOD OF USE,” and U.S.patent application Ser. No. 14/715,527, filed May 18, 2015, published asUS2016/0339158 A1 on Nov. 24, 2016, titled “FLUIDIC CONNECTOR FORNEGATIVE PRESSURE WOUND THERAPY,” the disclosure of each of which ishereby incorporated by reference in its entirety, including furtherdetails relating to embodiments of wound dressings, the wound dressingcomponents and principles, and the materials used for the wounddressings.

Additionally, some embodiments related to TNP wound treatment comprisinga wound dressing in combination with a pump or associated electronicsdescribed herein may also be used in combination or in addition to thosedescribed in International Application PCT/EP2016/059329 filed Apr. 26,2016, published as WO 2016/174048 on Nov. 3, 2016, entitled “REDUCEDPRESSURE APPARATUS AND METHODS,” the disclosure of which is herebyincorporated by reference in its entirety.

In some embodiments of wound closure devices described herein, increasedwound contraction can lead to increased tissue expansion in thesurrounding wound tissue. This effect may be increased by varying theforce applied to the tissue, for example by varying the negativepressure applied to the wound over time, possibly in conjunction withincreased tensile forces applied to the wound via embodiments of thewound closure devices. Further, there may be additional effects ontissues in close proximity to the filler, for example, the tissue isunder compression due to the reactive force of the elastic fillerpressing on the tissue. Such compression may result in in local hypoxiadue to occlusion of the blood vessels. In the wider peripheral tissue,this expansion may lead to blood vessel expansion. Further details areprovided in “NPWT settings and dressing choices made easy” by Malmsjoand Borgquist, published in Wounds International in May 2010, herebyincorporated by reference in its entirety. For example, in a wound thatis not at risk for ischemia, the increased and decreased blood flowcaused by pressure from the wound dressing is likely advantageous forwound healing. The increase in blood flow may improve oxygen andnutrient supply to the tissue, and improve penetration of antibioticsand the removal of waste. Additionally, the reduction in blood flow maystimulate angiogenesis, thereby promoting granulation tissue formation.

Wound Healing

One of skill in the art will understand that the embodiments describedherein, particularly with reference to Eulerian Video Magnification(EVM), are not merely applicable to situations involving NPWT. Rather,such embodiments may be broadly applicable to situations that do notnecessarily require NPWT, such as evaluating intact tissue or providingadditional treatments to wounds.

Wounds may be generally categorized as open or closed, often dependingupon how the wound is caused. As described above, the techniques may beapplied to both open and to closed wounds, depending on the particularsof the embodiment. Open wounds may be caused by a variety of events,including: incisions, lacerations, abrasions, punctures, penetration,amputation, and other means. Closed wounds may be caused by damage to ablood vessel resulting in formation of a hematoma, and/or by internalinjuries caused by crushing. Further, wounds may involve various layersof tissue, for example, shallower wounds may only involve the topmostlayers of the skin, while deeper wounds may involve underlyingsubcutaneous tissue layers such as the hypodermis, including underlyingconnective tissues and fatty layers. In certain embodiments, wounds mayeven encompass underlying internal organs, deep beneath the skin.Certain wounds, such as those caused by pressure injuries, may start tooccur within the deeper tissue layers without become evident on thesurface of the skin until much later.

In addition to NPWT treatments described above, wounds may be treated bya wide variety of techniques and materials. For example, wounds may betreated by debridement to remove dead and/or necrotic tissue. Wounds maybe treated with a with various type of dressings, including dry and wetdressings, chemically-impregnated dressings, foam dressing, hydrogeldressings, hydrocolloid dressings, film dressings, and other suitabledressings. Wounds may further be treated with bioactive molecules suchas antimicrobials, growth factors, anti-inflammatories, analgesics andother suitable treatments. Such treatments may be incorporated into theaforementioned dressings.

Further details regarding wounds and wound treatment, in particularwounds caused by pressure injuries may be found in the article “PressureInjuries (Pressure Ulcers) and Wound Care” by Kirman et al, published inMedscape March 2017, and hereby incorporated by reference in itsentirety. For example, the most common candidates for pressure ulcersinclude: elderly persons, persons who are chronically ill (such as thosewith cancer, stroke, or diabetes), persons who are immobile (e.g, as aconsequence of fracture, arthritis, or pain), persons who are weak ordebilitated, patients with altered mental status (e.g., from the effectsof narcotics, anesthesia, or coma), and/or persons with decreasedsensation or paralysis. Potential secondary factors include: illness ordebilitation that increases pressure ulcer formation, fever (increasesmetabolic demands), predisposing ischemia, diaphoresis which promotesskin maceration, incontinence which causes skin irritation andcontamination, edema, jaundice, pruritus, and xerosis (dry skin).Additionally, prevention of pressure ulcer injuries may include:scheduled body turning, appropriate bed positioning, protection of bonyprominences, skin care, control of spascity and prevention ofcontractures, use of support surfaces/specialty beds, nutritionalsupport, and maintenance of current levels of activity, mobility andrange of motion.

Negative Pressure System

FIG. 1 illustrates an embodiment of a negative or reduced pressure woundtreatment (or TNP) system 100 comprising a wound filler 130 placedinside a wound cavity 110, the wound cavity sealed by a wound cover 120.The wound filler 130 in combination with the wound cover 120 can bereferred to as wound dressing. A single or multi lumen tube or conduit140 is connected the wound cover 120 with a pump assembly 150 configuredto supply reduced pressure. The wound cover 120 can be in fluidiccommunication with the wound cavity 110. In any of the systemembodiments disclosed herein, as in the embodiment illustrated in FIG. 1, the pump assembly can be a canisterless pump assembly (meaning thatexudate is collected in the wound dressing or is transferred via tube140 for collection to another location). However, any of the pumpassembly embodiments disclosed herein can be configured to include orsupport a canister. Additionally, in any of the system embodimentsdisclosed herein, any of the pump assembly embodiments can be mounted toor supported by the dressing, or adjacent to the dressing.

The wound filler 130 can be any suitable type, such as hydrophilic orhydrophobic foam, gauze, inflatable bag, and so on. The wound filler 130can be conformable to the wound cavity 110 such that it substantiallyfills the cavity. The wound cover 120 can provide a substantially fluidimpermeable seal over the wound cavity 110. The wound cover 120 can havea top side and a bottom side, and the bottom side adhesively (or in anyother suitable manner) seals with wound cavity 110. The conduit 140 orlumen or any other conduit or lumen disclosed herein can be formed frompolyurethane, PVC, nylon, polyethylene, silicone, or any other suitablematerial.

Some embodiments of the wound cover 120 can have a port (not shown)configured to receive an end of the conduit 140. For example, the portcan be Renays Soft Port available from Smith & Nephew. In otherembodiments, the conduit 140 can otherwise pass through or under thewound cover 120 to supply reduced pressure to the wound cavity 110 so asto maintain a target or desired level of reduced pressure in the woundcavity. The conduit 140 can be any suitable article configured toprovide at least a substantially sealed fluid flow pathway between thepump assembly 150 and the wound cover 120, so as to supply the reducedpressure provided by the pump assembly 150 to wound cavity 110.

The wound cover 120 and the wound filler 130 can be provided as a singlearticle or an integrated single unit. In some embodiments, no woundfiller is provided and the wound cover by itself may be considered thewound dressing. The wound dressing may then be connected, via theconduit 140, to a source of negative pressure, such as the pump assembly150. The pump assembly 150 can be miniaturized and portable, althoughlarger conventional pumps such can also be used.

The wound cover 120 can be located over a wound site to be treated. Thewound cover 120 can form a substantially sealed cavity or enclosure overthe wound site. In some embodiments, the wound cover 120 can beconfigured to have a film having a high water vapor permeability toenable the evaporation of surplus fluid, and can have a superabsorbingmaterial contained therein to safely absorb wound exudate. It will beappreciated that throughout this specification reference is made to awound. In this sense it is to be understood that the term wound is to bebroadly construed and encompasses open and closed wounds in which skinis torn, cut or punctured or where trauma causes a contusion, or anyother surficial or other conditions or imperfections on the skin of apatient or otherwise that benefit from reduced pressure treatment. Awound is thus broadly defined as any damaged region of tissue wherefluid may or may not be produced. Examples of such wounds include, butare not limited to, acute wounds, chronic wounds, surgical incisions andother incisions, subacute and dehisced wounds, traumatic wounds, flapsand skin grafts, lacerations, abrasions, contusions, burns, diabeticulcers, pressure ulcers, stoma, surgical wounds, trauma and venousulcers or the like. The components of the TNP system described hereincan be particularly suited for incisional wounds that exude a smallamount of wound exudate.

Some embodiments of the system are designed to operate without the useof an exudate canister. Some embodiments can be configured to support anexudate canister. In some embodiments, configuring the pump assembly 150and tubing 140 so that the tubing 140 can be quickly and easily removedfrom the pump assembly 150 can facilitate or improve the process ofdressing or pump changes, if necessary. Any of the pump embodimentsdisclosed herein can be configured to have any suitable connectionbetween the tubing and the pump.

The pump assembly 150 can be configured to deliver negative pressure ofapproximately −80 mmHg, or between about −20 mmHg and 200 mmHg in someimplementations. Note that these pressures are relative to normalambient atmospheric pressure thus, −200 mmHg would be about 560 mmHg inpractical terms. The pressure range can be between about −40 mmHg and−150 mmHg. Alternatively a pressure range of up to −75 mmHg, up to −80mmHg or over −80 mmHg can be used. Also a pressure range of below −75mmHg can be used. Alternatively a pressure range of over approximately−100 mmHg, or even 150 mmHg, can be supplied by the pump assembly 150.

In operation, the wound filler 130 is inserted into the wound cavity 110and wound cover 120 is placed so as to seal the wound cavity 110. Thepump assembly 150 provides a source of a negative pressure to the woundcover 120, which is transmitted to the wound cavity 110 via the woundfiller 130. Fluid (e.g., wound exudate) is drawn through the conduit140, and can be stored in a canister. In some embodiments, fluid isabsorbed by the wound filler 130 or one or more absorbent layers (notshown).

Wound dressings that may be utilized with the pump assembly and otherembodiments of the present application include Renasys-F, Renasys-G,Renasys AB, and Pico Dressings available from Smith & Nephew. Furtherdescription of such wound dressings and other components of a negativepressure wound therapy system that may be used with the pump assemblyand other embodiments of the present application are found in U.S.Patent Publication Nos. 2011/0213287, 2011/0282309, 2012/0116334,2012/0136325, and 2013/0110058, which are incorporated by reference intheir entirety. In other embodiments, other suitable wound dressings canbe utilized.

Pump Assembly and Canister

FIG. 2A illustrates a front view of a pump assembly 230 and canister 220according to some embodiments. As is illustrated, the pump assembly 230and the canister are connected, thereby forming a negative pressurewound therapy device. The pump assembly 230 can be similar to or thesame as the pump assembly 150 in some embodiments.

The pump assembly 230 includes one or more indicators, such as visualindicator 202 configured to indicate alarms and visual indicator 204configured to indicate status of the TNP system. The indicators 202 and204 can be configured to alert a user, such as patient or medical careprovider, to a variety of operating or failure conditions of the system,including alerting the user to normal or proper operating conditions,pump failure, power supplied to the pump or power failure, detection ofa leak within the wound cover or flow pathway, suction blockage, or anyother similar or suitable conditions or combinations thereof. The pumpassembly 230 can comprise additional indicators. The pump assembly canuse a single indicator or multiple indicators. Any suitable indicatorcan be used such as visual, audio, tactile indicator, and so on. Theindicator 202 can be configured to signal alarm conditions, such ascanister full, power low, conduit 140 disconnected, seal broken in thewound seal 120, and so on. The indicator 202 can be configured todisplay red flashing light to draw user's attention. The indicator 204can be configured to signal status of the TNP system, such as therapydelivery is ok, leak detected, and so on. The indicator 204 can beconfigured to display one or more different colors of light, such asgreen, yellow, etc. For example, green light can be emitted when the TNPsystem is operating properly and yellow light can be emitted to indicatea warning.

The pump assembly 230 includes a display or screen 206 mounted in arecess 208 formed in a case of the pump assembly. The display 206 can bea touch screen display. The display 206 can support playback ofaudiovisual (AV) content, such as instructional videos. As explainedbelow, the display 206 can be configured to render a number of screensor graphical user interfaces (GUIs) for configuring, controlling, andmonitoring the operation of the TNP system. The pump assembly 230comprises a gripping portion 210 formed in the case of the pumpassembly. The gripping portion 210 can be configured to assist the userto hold the pump assembly 230, such as during removal of the canister220. The canister 220 can be replaced with another canister, such aswhen the canister 220 has been filled with fluid.

The pump assembly 230 includes one or more keys or buttons configured toallow the user to operate and monitor the operation of the TNP system.As is illustrated, there buttons 212 a, 212 b, and 212 c (collectivelyreferred to as buttons 212) are included. Button 212 a can be configuredas a power button to turn on/off the pump assembly 230. Button 212 b canbe configured as a play/pause button for the delivery of negativepressure therapy. For example, pressing the button 212 b can causetherapy to start, and pressing the button 212 b afterward can causetherapy to pause or end. Button 212 c can be configured to lock thedisplay 206 or the buttons 212. For instance, button 212 c can bepressed so that the user does not unintentionally alter the delivery ofthe therapy. Button 212 c can be depressed to unlock the controls. Inother embodiments, additional buttons can be used or one or more of theillustrated buttons 212 a, 212 b, or 212 c can be omitted. Multiple keypresses or sequences of key presses can be used to operate the pumpassembly 230.

The pump assembly 230 includes one or more latch recesses 222 formed inthe cover. In the illustrated embodiment, two latch recesses 222 can beformed on the sides of the pump assembly 230. The latch recesses 222 canbe configured to allow attachment and detachment of the canister 220using one or more canister latches 221. The pump assembly 230 comprisesan air outlet 224 for allowing air removed from the wound cavity 110 toescape. Air entering the pump assembly can be passed through one or moresuitable filters, such as antibacterial filters. This can maintainreusability of the pump assembly. The pump assembly 230 includes one ormore strap mounts 226 for connecting a carry strap to the pump assembly230 or for attaching a cradle. In the illustrated embodiment, two strapmounts 226 can be formed on the sides of the pump assembly 230. In someembodiments, various of these features are omitted or various additionalfeatures are added to the pump assembly 230.

The canister 220 is configured to hold fluid (e.g., exudate) removedfrom the wound cavity 110. The canister 220 includes one or more latches221 for attaching the canister to the pump assembly 230. In theillustrated embodiment, the canister 220 comprises two latches 221 onthe sides of the canister. The exterior of the canister 220 can formedfrom frosted plastic so that the canister is substantially opaque andthe contents of the canister and substantially hidden from plain view.The canister 220 comprises a gripping portion 214 formed in a case ofthe canister. The gripping portion 214 can be configured to allow theuser to hold the pump assembly 220, such as during removal of thecanister from the apparatus 230. The canister 220 includes asubstantially transparent window 216, which can also include graduationsof volume. For example, the illustrated 300 mL canister 220 includesgraduations of 50 mL, 100 mL, 150 mL, 200 mL, 250 mL, and 300 mL. Otherembodiments of the canister can hold different volume of fluid and caninclude different graduation scale. For example, the canister can be an800 mL canister. The canister 220 comprises a tubing channel 218 forconnecting to the conduit 140. In some embodiments, various of thesefeatures, such as the gripping portion 214, are omitted or variousadditional features are added to the canister 220. Any of the disclosedcanisters may include or may omit a solidifier.

FIG. 2B illustrates a rear view of the pump assembly 230 and canister220 according to some embodiments. The pump assembly 230 comprises aspeaker port 232 for producing sound. The pump assembly 230 includes afilter access door 234 with a screw for removing the access door 234,accessing, and replacing one or more filters, such as antibacterial orodor filters. The pump assembly 230 comprises a gripping portion 236formed in the case of the pump assembly. The gripping portion 236 can beconfigured to allow the user to hold the pump assembly 230, such asduring removal of the canister 220. The pump assembly 230 includes oneor more covers 238 configured to as screw covers or feet or protectorsfor placing the pump assembly 230 on a surface. The covers 230 can beformed out of rubber, silicone, or any other suitable material. The pumpassembly 230 comprises a power jack 239 for charging and recharging aninternal battery of the pump assembly. The power jack 239 can be adirect current (DC) jack. In some embodiments, the pump assembly cancomprise a disposable power source, such as batteries, so that no powerjack is needed.

The canister 220 includes one or more feet 244 for placing the canisteron a surface. The feet 244 can be formed out of rubber, silicone, or anyother suitable material and can be angled at a suitable angle so thatthe canister 220 remains stable when placed on the surface. The canister220 comprises a tube mount relief 246 configured to allow one or moretubes to exit to the front of the device. The canister 220 includes astand or kickstand 248 for supporting the canister when it is placed ona surface. As explained below, the kickstand 248 can pivot between anopened and closed position. In closed position, the kickstand 248 can belatched to the canister 220. In some embodiments, the kickstand 248 canbe made out of opaque material, such as plastic. In other embodiments,the kickstand 248 can be made out of transparent material. The kickstand248 includes a gripping portion 242 formed in the kickstand. Thegripping portion 242 can be configured to allow the user to place thekickstand 248 in the closed position. The kickstand 248 comprises a hole249 to allow the user to place the kickstand in the open position. Thehole 249 can be sized to allow the user to extend the kickstand using afinger.

FIG. 2C illustrates a view of the pump assembly 230 separated from thecanister 220 according to some embodiments. The pump assembly 230includes a vacuum attachment, connector, or inlet 252 through which avacuum pump communicates negative pressure to the canister 220. The pumpassembly aspirates fluid, such as gas, from the wound via the inlet 252.The pump assembly 230 comprises a USB access door 256 configured toallow access to one or more USB ports. In some embodiments, the USBaccess door is omitted and USB ports are accessed through the door 234.The pump assembly 230 can include additional access doors configured toallow access to additional serial, parallel, or hybrid data transferinterfaces, such as SD, Compact Disc (CD), DVD, FireWire, Thunderbolt,PCI Express, and the like. In other embodiments, one or more of theseadditional ports are accessed through the door 234.

Eulerian Video Magnification

Novel techniques for the analysis of small changes in pixels over timehave been developed using a technique called “Eulerian VideoMagnification” (EVM). EVM can act to amplify these extremely smallchanges in pixels over time, therefore allowing detection of previouslyundetectable changes. For example, EVM may be applied to standard videosuch as those taken by an optical camera. Minute visual changes in thestate of the object and/or person being videoed can then be amplified byEVM and therefore be detected. For example, EVM can detect blood flowunder the skin or breathing, such as in neonatal infants. Additionaldetails regarding EVM are provided in an article published by theMassachusetts Institute of Technology titled “Eulerian VideoMagnification for Revealing Subtle Changes in the World” by Wu et al,hereby incorporated by reference in its entirety.

EVM serves to amplify subtle changes in any spatial location in a video(such as a pixel) over time. Such subtle changes may not be visible tothe naked eye, therefore EVM allows for the detection of minutephenomena undetectable under normal viewing and monitoring. Such videocan be collected via any suitable means and is not simply limited tovideo collected within the visible light spectra. For example, video maybe collected via: camera, charge-coupled devices (CCDs), oxygensaturation (spO2) detector, magnetic resonance imaging, x-ray imaging,infrared imaging or any form of video data collection over time. Theamplified change in a pixel value can be the result of changes due tovariations in color, motion, or any other suitable change depending uponthe type of video. For example, video of spO2 measurements in aparticular area could output as a value, such as a color, therefore EVMapplied to such a video could detect subtle changes in spO2. Asdescribed above, additional details regarding EVM are provided in anarticle published by the Massachusetts Institute of Technology titled“Eulerian Video Magnification for Revealing Subtle Changes in the World”by Wu et al.

As described by Wu et al, spatial and temporal processing can be used toemphasize subtle temporal changes in a video. An embodiment of thisprocess is illustrated in FIG. 3 . In brief, the EVM system 300 firstdecomposes 304 the input video sequence 302 into different spatialfrequency bands 306, and applies the same temporal filter to all bands308. The filtered spatial bands 310 are then amplified by a given factorα 312, added back to the original signal 314, and collapsed to generatethe output video 316.

As described by Wu, first, the video sequence is decomposed intodifferent spatial frequency bands. These bands might be magnifieddifferently because (a) they might exhibit different signal-to-noiseratios or (b) they might contain spatial frequencies for which thelinear approximation described later for motion magnification does nothold. In the latter case, amplification for these bands may be reducedto suppress artifacts. When the goal of spatial processing is simply toincrease the temporal signal-to-noise ratio by pooling multiple pixels,the frames of the video may be subjected to a spatially low-pass filterand down sampled for computational efficiency. In the general case,however, a full Laplacian pyramid [Burt and Adelson 1983] may beperformed, followed by temporal processing on each spatial band. Thetime series corresponding to the value of a pixel in a frequency bandmay be considered and a bandpass filter may be applied to extract thefrequency bands of interest. For example, we might select frequencieswithin 0.4-4 Hz, corresponding to 24-240 beats per minute, if we wish tomagnify a pulse. If we are able to extract the pulse rate, we can use anarrow band around that value. The temporal processing is uniform forall spatial levels, and for all pixels within each level. We thenmultiply the extracted band-passed signal by a magnification factor.This factor can be specified by the user, and may be attenuatedautomatically according to guidelines described below. Possible temporalfilters are also discussed below. Next, we add the magnified signal tothe original and collapse the spatial pyramid to obtain the finaloutput. Since natural videos are spatially and temporally smooth, andsince our filtering is performed uniformly over the pixels, our methodimplicitly maintains spatiotemporal coherency of the results.

To explain the relationship between temporal processing and motionmagnification, we consider the simple case of a 1D signal undergoingtranslational motion. This analysis generalizes directly tolocally-translational motion in 2D. Let I(x; t) denote the imageintensity at position x and time t. Since the image undergoestranslational motion, we can express the observed intensities withrespect to a displacement function δ(t), such that I(x; t)=f(x+δ(t)) andI(x; 0)=f(x). The goal of motion magnification is to synthesize thesignal Î(x,t)=ƒ(x+(1+α)δ(t)) for some amplification factor α.

Assuming the image can be approximated by a first-order Taylor seriesexpansion, we write the image at time t, ƒ(x+δ(t)) in a first-orderTaylor expansion about x, as

${I\left( {x,t} \right)} \approx {{f(x)} + {{\delta(t)}{\frac{\partial{f(x)}}{\partial x}.}}}$

Let B(x; t) be the result of applying a broadband temporal bandpassfilter to I(x; t) at every position x (picking out everything exceptf(x) in the above equation). For now, let us assume the motion signal,(t), is within the passband of the temporal bandpass filter (we willrelax that assumption later). Then we have

${B\left( {x,t} \right)} = {{\delta(t)}{\frac{\partial{f(x)}}{\partial x}.}}$

In our process, we then amplify that bandpass signal by and add it backto I(x; t), resulting in the processed signalÎ(x,t)=I(x,t)+αB(x,t).

Combining the previous equations, we now have

${\overset{\sim}{I}\left( {x,t} \right)} \approx {{f(x)} + {\left( {1 + \alpha} \right){\delta(t)}{\frac{\partial{f(x)}}{\partial x}.}}}$

Assuming the first-order Taylor expansion holds for the amplified largerperturbation, (1+α)δ(t), we can relate the amplification of thetemporally bandpassed signal to motion magnification. The processedoutput is simplyÎ(x,t)≈ƒ(x+(1+α)δ(t)).

This shows that the processing magnifies motions—the spatialdisplacement δ(t) of the local image f(x) at time t, has been amplifiedto a magnitude of (1+α). For a low frequency cosine wave and arelatively small displacement, (t), the first-order Taylor seriesexpansion serves as a good approximation for the translated signal attime t+1. When boosting the temporal signal by and adding it back toI(x; t), we approximate that wave translated by (1+α)δ. For quicklychanging image functions (i.e., high spatial frequencies), f(x), thefirst-order Taylor series approximations becomes inaccurate for largevalues of the perturbation, 1+αδ(t), which increases both with largermagnification and motion δ(t).

As a function of spatial frequency, co, we can derive a guide for howlarge the motion amplification factor, α, can be, given the observedmotion δ(t). For the processed signal, I (x, t) to be approximatelyequal to the true magnification motion, I(x,t), we seek the conditionsunder which:

$\left. {{\overset{\sim}{I}\left( {x,t} \right)} \approx {\hat{I}\left( {x,t} \right)}}\Rightarrow{{{f(x)} + {\left( {1 + \alpha} \right){\delta(t)}\frac{\partial{f(x)}}{\partial x}}} \approx {f\left( {x + {\left( {1 + \alpha} \right){\delta(t)}}} \right)}} \right.$

Further rearrangement via the addition law of cosines and use of thefollowing approximation:cos(βωδ(t))≈1sin(βωδ(t))≈βδ(t)ω

leads to the following guideline:

${\left( {1 + \alpha} \right){\delta(t)}} < {\frac{\lambda}{8}.}$

This guideline provides the largest motion amplification factor, a,compatible with accurate motion magnification of a given video motionδ(t) and image structure spatial wavelength, λ. In some videos,violating the approximation limit can be perceptually preferred and weleave the λ cutoff as a user-modifiable parameter in the multiscaleprocessing.

In some embodiments, to process an input video by Eulerian videomagnification, there are four steps a user needs to take: (1) select atemporal bandpass filter; (2) select an amplification factor, a; (3)select a spatial frequency cutoff (specified by spatial wavelength, λc)beyond which an attenuated version of a is used; and (4) select the formof the attenuation for α, either force a to zero for all λ<λc, orlinearly scale a down to zero. The frequency band of interest can bechosen automatically in some cases, but it is often important for usersto be able to control the frequency band corresponding to theirapplication. In our real-time application, the amplification factor andcut-off frequencies are all customizable by the user.

One of skill in the art will understand that use of the term “color” asused herein this section and throughout the specification, may not onlyrepresent the optical spectrum. The word “color” may at times be usedcolloquially to identify a spectral frequency range (which may or maynot be in the visible range). One of skill in the art will furtherunderstand that in embodiments, the techniques described herein may alsofunction without the use of EVM, for example by detecting a change ingreen/red. However, such systems without EVM may have a significantreduction in sensitivity.

Of particular interest for the evaluation of intact tissue sites or inwounds, in some embodiments, Eulerian Video Magnification may be used toamplify subtle changes in pixel values relating to color using videocollected from a CCD camera or RGB color detector. In some embodiments,a camera or RGB color detector may be combined with one or more standardLEDs to light the wound for visualization. For example, within an intactpatch of skin or a wound bed, color changes may be indicative offavorable blood flow. For example, a value in the red spectrum via colordetection may indicate blood flow, therefore, if the difference betweenthe peak value and trough value of the color is small then it suggeststhat there is not much blood flow. Conversely, if the difference betweenthe peak value and the trough value is relatively high, then this mayindicate good blood flow to the tissue area.

Further, if the value is less red than there is likely to beinsufficient oxygen. In some embodiments, color could also be used togenerate an indication of blood oxygen (or with the light sourcemodified to sense SP02 directly), to minimize the likelihood of damageto the capillaries upon treatment and to act as an alert ifexsanguination does occur, potentially mitigating against potential harmthat may be caused by application of NPWT. In some embodiments, EVM maybe used on skin near a wound to monitor the motion of the adjacent skindue therefore identify whether the blood pulse is making it to the areaof concern. Advantageously, absolute values need not be monitored toidentify potential issues within the wound or tissue, instead monitoringof the difference in values is sufficient.

Pressure Injury Monitoring and Treatment

Pressure injuries (also known as pressure ulcers or bedsores) areinjuries to soft tissues such as the skin and/or underlying tissue thatoccur due to obstructed blood flow caused by pressure. Pressure injuriesare common on patients with limited mobility such as the elderly or thehandicapped. Particularly susceptible to pressure ulcers are patientswho are confined to a particular location such as a bed or wheelchair.Of particular interest in the field of medicine is the identification ofpressure ulcers early on, before they become a serious injury. However,it can often be difficult to identify an area where a potential pressureinjury will form due to early stage damage to the underlying tissue.Such damage may not be detectible by the naked eye by a clinician, butmay be detectable by a monitoring system supported by EVM.

FIG. 4 illustrates an embodiment of a system for pressure ulcerdetection. However, one of skill in the art will understand that such asystem may also be easily applied to other potential injuries or skinconditions. Further, the systems described here in relation to FIG. 4are not limited to intact tissue, such systems may also be applied to anopen wound.

FIG. 4 depicts an embodiment of a monitoring and treatment system 1000incorporating EVM. Sensor construct 1002, may be positioned over atissue sit of interest. In some embodiments, the sensor construct 1002may comprise: one sensor, two sensors, three sensors, four sensors, fivesensors, at least about 10 sensors, at least about 20 sensors, or morethan 20 sensors. The sensor construct can be positioned above the tissuesite, at an angle to the tissue site, under the tissue site, below thepatient, or in any suitable position. In some embodiments, the sensorconstruct may collect video of a specific tissue site or the entirety ofthe patient.

One of skill in the art will understand that the sensor construct is notlimited to a specific form or shape. For example, the sensor constructmay be in the form of a mounted camera, a freely held camera, or a smartphone. The sensor construct may be part of a dressing or part ofhospital bed or wheelchair. In some embodiments, a sensor construct maybe in the form of a bundle of optical fibers that are contained within ablanket, bed system, sheet, and/or clothing. Such a form may allow forbetter visualization of a limited mobility patient confined to a bed. Insome embodiments, the sensor could be positioned above a blanket orclothing and utilize visualization techniques that are not as limited byopaque objects, such as IR. Such a non-limited sensor construct may evenbe placed below a hospital bed or chair, providing visualization of thepatient through the underside of the bed. The sensor construct may be inthe form of a pressure matte, providing detailed information in closecontact with the patient.

In some embodiments, the sensor(s) may collect information such as: pH,temperature, light, conductivity, impedance, capacitance, or othercharacteristics of the wound. In some embodiments, the sensors canprovide information about the blood flow, moistness or dryness of thewound, lactate levels, or other characteristics of the wound. In someembodiments, all manner of sensor(s) may be incorporated in the systemand they may be configured to measure parameters such as temperature,pH, oxygen, carbon dioxide, millimeter wave frequencies, conductivity,inductance, lactate, metallomatrix proteases, growth factors, opticalabsorption and reflectance including at infrared and UV frequencies andfluorescence, infection (level of bacterial burden and types ofbacteria), or other characteristics of the tissue/wound environment. Incertain embodiments, ultrasonic sensors with or without transducers maybe used.

In some embodiments, thermistors or thermocouples may be used in placeof the RGB sensor/CCD and light source described above. A grid or matrixof such sensors could be mounted and close-coupled to the tissue. Thesecould be used in concert with other sensors (e.g. optical or EEG/ECG) toallow separation of the heart rate from the temperature noise of theenvironment (i.e. identifying the temperature changes that occur at thefrequency of the heart pulse).

In some embodiments, coils for the generation of magnetic fields and/orRF signal may be placed within a dressing or in close proximity to thepatient in place of or in addition to the CCD/RGB sensor. Coils may bemounted co-axially either nested or offset within the dressing. In someembodiments, a separate probe may be used to contain the coils, such aprobe may be held against the tissue and transmit signals by wired orwireless connection. In certain embodiments, one or more accelerometersmay be used for additional data input. Wobble switches and/or gyroscopesmay also be used.

As described above, optical sensors may be used to measure woundappearance using an RGB sensor with an illumination source. In certainembodiments, another suitable optical sensor may be used. Both the RGBsensor and the illumination source may be pressed up against the skin,such that light would penetrate into the tissue and take on the spectralfeatures of the tissue itself. Light propagation in tissue is dominatedby two major phenomena, scattering and attenuation. For attenuation, aslight passes through tissue, the intensity is lost due to absorption byvarious components of the tissue. Blue light tends to be attenuatedheavily, whilst light at the red end of the spectrum tends to beattenuated least.

Scattering processes are more complex, and have various regimes whichmust be considered. The first aspect of scattering is based on the sizeof the scattering center compared with the wavelength of incident light.If the scattering center is much smaller than the wavelength of light,then Rayleigh scattering can be assumed. If the scattering center is onthe order of the wavelength of light, then a more detailed Miescattering formulation must be considered. Another factor involved inscattering light is the distance between input and output of thescattering media. If the mean free path of the light (the distancebetween scattering events) is much larger than the distance travelled,then ballistic photon transport is assumed. In the case of tissue,scatting events are approximately 100 microns apart—so a 1 mm pathdistance would effectively randomize the photon direction and the systemwould enter a diffusive regime.

Ultra-bright light emitting diodes (LEDs), an RGB sensor, and polyesteroptical filters can be used as components of the optical sensors tomeasure tissue color differentiation. Infrared and/or NIR of FIR mayalso be used. For example, because surface color can be measured fromreflected light, a color can be measured from light which has passedthrough the tissue first for a given geometry. This can include colorsensing from diffuse scattered light, from an LED in contact with theskin. In some embodiments, an LED can be used with an RGB sensor nearbyto detect the light which has diffused through the tissue. The opticalsensors can image with diffuse internal light or surface reflectedlight. Optical sensors can also be used to measure autoflouresence.Autoflourescense is used because the tissue is absorbing light at onewavelength, and emitting at another. Additionally, dead tissue may notauto-fluoresce and so this could be a very strong indication as to ifthe tissue is healthy or not. Due to blue light (or even UV light)having such a short penetration depth, it may be very useful for exampleto have a UV light with a red sensitive photodiode nearby (or some otherwavelength shifted band) to act as a binary test for healthy tissue,which would auto-fluoresce at a very particular wavelength. In certainembodiments, an RGBW sensor may be used, but utilizing the white channelas the baseline to normalize the relative values of the RG and B.

Returning to the embodiment of FIG. 4 , sensor construct 1002 withsensor 1004 may be positioned over a tissue site 1006. The sensor 1004may be in communication 1012 with a controller 1014, via any suitablewired or wireless means. In certain embodiments, the sensor construct,sensor, and controller may all be one integrated apparatus, such as asmartphone, tablet, or other suitable computing device such as disclosedherein this section or elsewhere in the specification. In someembodiments, the sensor construct and the controller may be physicallyseparated.

The communication from the sensor to the controller may be one-way, withthe controller only receiving information from the sensor. However,alternatively, the communication 1012 between the sensor and thecontroller may be two-way with the sensor sending information to thecontroller but also receiving instructions and/or information from thecontroller. Controller 1014 may then be in communication, via wired orwireless means, with an output or alerting element 1010. Alertingelement 1010 may be any suitable device configured to provide an alert.For example, the alert may be one or more of audible, haptic, or visual.The alert indicates to a caregiver that a pressure injury will form ormay have already formed. Such an alert allows the caregiver to takepre-emptive action to avoid a pressure injury, such as to engage inpressure offloading of the patient such as by turning, adding stressrelievers, performing treatments, or other suitable means.

In some embodiments, the alerting element may be part of a singleintegrated device with the sensor construct, sensor, controller, andalerting element. For example, such a device may be a smart phone,tablet, or other suitable computing device such as disclosed herein thissection or elsewhere in the specification. In particular embodiments,the alerting element is physically separate from the sensor andcontroller. However, various embodiments the alerting element may beintegrated with the sensor construct but not the controller, or thealerting element may be integrated with the controller but not thesensor construct.

The controller may be any processing device capable of executingsoftware, such as disclosed herein this section or elsewhere in thespecification. For example, the processing device may be a processor,PC, tablet, smartphone, or other computer capable of running hostsoftware.

When the system 1000 is operating, the sensor 1004 collects video datafrom the tissue site 1006 over time. This video data may be collectedand stored to be transmitted to the controller 1014 at periodicintervals and/or the video data may be continuously transmitted to thecontroller. The tissue site video data collected by the sensor 1004 maybe of any data potentially collected from any sensor disclosed hereinthis section or elsewhere in the specification, but suitably visibleoptical data or IR data. In some embodiments, the sensor may collectvideo of the tissue site indicative of tissue that may have poor bloodflow. As will be described in greater detail below, in such instancesthe alerting element is configured to deliver an alert to direct acaregiver to the possibility of formation of a pressure injury. In someembodiments, the sensor 1004 may detect the edge of a wound 1006 andthen collect video of the edge of the wound, for example collectingoptical data including motion and color information. As describedpreviously, EVM can be used to detect very subtle changes in individuallocations/pixels within a video. In certain embodiments, EVM may beapplied to a single pixel. Such a single pixel may be from a singlesensor or combined/averaged from multiple sensors. In some embodiments,multiple pixels may be drawn from a single sensor or form multiplesensors such as in an array. For motion detection (i.e. identificationof tissue movement due to blood pulsing within it as describedelsewhere), multiple, closely aligned pixels may be required. However,in some embodiments, single pixels or multiple pixels from a singlesensor may be used.

Video data collected by the sensor may then be transmitted to thecontroller 1014, whereby the controller applies EVM to the video. Asdescribed previously, EVM, can be used to detect very subtle changes inindividual locations/pixels within a video. Changes in color and/ormotion may be indicative of blood flow to the tissue, poor blood flowmay indicate the potential for a pressure injury. Further, less redtissue may indicate the existence of pressure limiting blood flow toparticular tissue site.

As will be described in greater detail below, change in color, motion,or another parameter may indicate that an alert should be generated bythe alerting element. If an alert is merited, the controller maycommunicate 1016 with the alerting element 1010 and direct the alertingelement 1010 to generate an alert. Such communication may be in the formof a feed-back loop, allowing for the alerting element to continue toprovide alerts until the tissue site is no longer at risk for a pressureinjury. In some embodiments, the alert can become progressively moreinsistent, via increase in sound, light, or other suitable means, if noaction is taken. The alert may vary in intensity, depending upon therisk of formation of a pressure injury and/or the severity of thepressure injury.

In some embodiments, time series analysis algorithms such AutoRegressive Integrated Moving Average (ARIMA), Generalized AutoregressiveConditional Heteroskedasticity (GARCH), or Cusum (or cumulative sum) canbe used to determine changes in values between pixelslocations in videoframes over time, such as described herein this section or elsewhere inthe specification. For example, indicative of blood flow or motion.Cusum can be defined as the running sum of the difference between eachsample and the mean (e.g., in the absence of change, Cusum is zero).Cusum can be used to track variations in the underlying variable,including one or more of redness, delta-red, motion, or a calculatedtreatment parameter. Determined Cusum value or values can be compared toone or more thresholds to determine blood flow and/or motion and/or anysuitable value disclosed herein this section or elsewhere in thespecification.

In some embodiments, EVM may be used detect very slight movements ormotion of the skin and underlying tissue such as tremors or vibration ofthe skin and underlying tissue. Such tremors or vibration of the skinmay be used for diagnosis, such as via any method described herein thissection or elsewhere in the specification. In some embodiments,vibration or tremors may be used to diagnose neurological diseases suchas multiple sclerosis or Parkinson's disease. Further, identification oftremors or vibration may be utilized to detect muscle strain. Forexample, a video image may be collected of a tissue site via anysuitable method disclosed herein, followed by amplification via EVM.Such amplified video may then be analyzed to determine an amount ofvibration/tremors, which can then compared to a threshold associatedwith Parkinson's disease or another similar disease. If thevibration/tremor of the tissue exceeds a threshold, then an alert may begenerated such as any alert disclosed herein this section or elsewherein the specification.

In certain embodiments, a proportional integral derivative algorithm(PID) style loop may be used by the NPWT pump, to ensure that theintegrated blood flow is suitable to maintain the tissue in anacceptable condition and optimal pressure may be used to ensure optimalblood flow without producing excessive blood flow. PID style loops arewell-known in the art for adjusting the output of a pump as a processvariable changes. In certain embodiments, the response to the treatmentparameter measurements may be self-optimizing such the software mayexplore optimum responses, per a change in treatment parameter byexamining the treatment/response curve. For example, if a particularchange in a variable results in a dramatic shift in treatment parameter,the system may adjust to only change the output for a desired amount.For example, a variable may be adjusted until a maximum difference inthe EVM output is achieved. In certain embodiments, it may beadvantageous to build in a delay between therapy adjustments to allowtime for the body to respond to the previous change in therapy.

The acceptable red-delta value could be modified slightly (by theclinician) to allow for pain-susceptible patients where beneficial butsub-optimal therapy is preferable to pain. A continuous high-red value(with minimal red-delta) would also be an indicator of bleeding, one ofthe highest risks of NPWT. Such a control system, may also be suitablefor pain management and bleeding-identification systems integrated intosoftware packages, such as software systems associated with NPWT pumpsystems. For example, while a specific location of bleeding may bedetected as pulsatile, once blood flows away from the breach it will nolonger have a pulse so the color maybe identified as red and not vary atthe pulse rate Thus, such an indicator can be identified as bleeding andflagged as a cause for immediate intervention, therefore trigger theshut-down of NPWT to minimize exsanguination before the intervention isachieved.

Advantageously, the use of EVM allows the system to be responsive tochanges at the tissue site, rather than simply being responsive toclinician observations. Such a system identifies the true blood flowwithin the specific patient. Current “standard” protocols requireturning of a patient after a specific time (a shorter time for higherrisk patients). The use of the system of FIG. 4 does not require anysubjective assessments of the risk to the patient, instead the systemdirectly identifies whether blood is being restricted from the tissuetherefore minimising unnecessary intervention while ensuring that allrequired intervention is performed.

Such a reactive system may also be pro-active in avoiding ischemia, aslow blood flow could be detected early and treated before traditionaldetection. Further, the system 1000 may allow for treatment of oedema byproviding an alert upon the identification of areas of oedema, therebyminimizing oedema by increasing effective compression.

FIG. 5A depicts an embodiment of a method of EVM processing incombination with an alerting element 1100, providing greater detail onthe steps taken from collection of video data to the alert shown abovein FIG. 4 . Although FIG. 5A makes reference to “modules,” one of skillin the art will understand that such modules may be software steps thatmay be completed on one or more computing devices, such as thecontroller described above in relation to FIG. 4 . Such computingdevices may be any computing device disclosed herein this section orelsewhere in the specification, for example a controller, smartphone,server, or general computer such as a laptop or desktop. In the firststep, a video capture device 1102, such as a camera or other sensordevice, such as disclosed herein this section or elsewhere in thespecification, collects video of a tissue site of interest. Video may betaken in any suitable manner or suitable location such as describedherein this section or elsewhere in the specification.

Next, a video clip of a desired length 1104, for example 10 seconds, iscollected and stored 1104. It will be understood by one of skill in theart that the video clip may be of any suitable length, for example,about: 1 second, 5 seconds, 10 seconds, 15 seconds, 30 seconds, 60seconds, 5 minutes, 1 hours, 12 hours, 24 hours, or more than 24 hours.Further, in certain embodiments, the video is continuously transmittedand continuously processed for analysis. The embodiment disclosed inFIG. 5A may be performed with clips of video or with continuouslytransmitted video. In some embodiments, the video may contain at leastabout: 5 frames per second, 10 frames per second, 20 frames per second,30 frames per second, 45 frames per second, 60 frames per second, 75frames per second, 90 frames per second, 120 frames per second, or morethan 120 frames per second.

Once the video has been captured, the values of each location/pixelwithin the video may be magnified via EVM 1106. Such an EVM algorithmmay be executed within any suitable software medium, for example MATLABcode. In some embodiments involving a video taken with a standard camerain the visible light spectrum, the EVM algorithm may serve to amplifythe color values of the image. For example, the EVM algorithm mayamplify the red color values within the video. As described above,redness may be an indicator of blood perfusion to a particular tissue.

Once the video clip or continuously streamed video has been processed, a“treatment parameter” is determined. For example, if a change in rednessis of interest, the change in redness or delta-red may be determined forevery location and/or pixel of interest and used in the calculation ofthe treatment parameter 1108. In some embodiments, the treatmentparameter may be calculated by the following steps 1110. First, a regionor regions of interest are set within a video frame, by selecting one ormore pixels within a particular area of the video frame.

Next, the pixels within the region are averaged to provide an averagevalue per region per frame. The averaging process may incorporatesophistication to eliminate outliers that may be introduced in to thesystem. Then, an array is generated for the average values over time asadditional data is collected with each consecutive frame of the video.From these consecutive frames, the highest values and lowest values maybe collected, for example the highest and lowest red values. Then, theaverage peak value may be calculated for the highest values and theaverage trough value may be calculated from the lowest values.Subtracting this highest average peak value from the lowest averagetrough value then gives a single value. This value can then becalibrated 1112 to equate to a single parameter number, referred to asthe “treatment parameter.” As will be described below, the “treatmentparameter” can be compared to a value in a lookup table 1116 to indicatewhether a NPWT device should increase or decrease application ofnegative pressure 1118. If the treatment parameter is determined fromchanges in red color within a video, then higher treatment parameterswould tend to indicate good blood perfusion, while lower treatmentparameters would tend to indicate poor blood flow.

As depicted in FIG. 5B, which can be implemented by a controller, incertain embodiments, to reduce the use of a high-rate sampling, multipleframes could be combined to provide a signal at a lower frame rate. Forexample, the values from frame 1 and frame 2 may be combined, along withthe values from frame 3 and frame 4, and so on 1202. Then thecombination of 1+2 may be compared with the value of 3+4 to identifyboth the highest and lowest signals for us in calculation of thetreatment parameter. In some embodiments, the combined values could becalculated in a different manner 1204, for example, by combining frames2 and 3, to be compared to a combination of frames 4 and 5, etc. Oncethe values within each frame are combined, then the amplitude of thechange in values may be calculated, in a similar fashion as describedabove by subtraction the average trough value from the average peakvalue. The treatment parameter may be calculated from changes in redvalue in a video that has undergone EVM. However, in furtherembodiments, any particular color value may be used such as blue orgreen. Further, any particular value may be used that can be derivedfrom video generated by any of the sensors disclosed herein this sectionor elsewhere in the specification, such as spO2 or infrared.

In certain embodiments, a possible analysis step may be to integrateblood flow values over time, potentially identifying whether thecumulative restriction of blood flow indicates a risk of pressureinjury. Such an indicated risk may trigger an alarm such as describedherein this section or elsewhere in the specification.

Returning to FIG. 5A, once the treatment parameter has been calculated,the controller may compare the treatment parameter 1114 to a pre-setdesired value or range. Such a desired value or range may be pre-set bythe controller or by a clinician. Such a desired value or range may bedetermined from literature, via experimentation, via algorithm, or viaother suitable means. Regardless, the use of a desired value or rangeallows the controller to compare the calculated treatment parameter tothe desired value or range in order to direct the alerting element toproduce an alert. If the treatment parameter remains at a desired valueor range then no alert may be generated, or an indicator may begenerated that indicates healthy tissue.

In certain embodiments, the response to the treatment parametermeasurements may be self-optimizing such the software may exploreoptimum responses, per a change in treatment parameter by examining thetreatment/response curve. For example, if a particular change in avariable results in a dramatic shift in treatment parameter, the systemmay adjust to only change the variable for a desired amount. Forexample, a variable may be adjusted until a maximum difference in theEVM output is achieved. In certain embodiments, it may be advantageousto build in a delay between therapy adjustments to allow time for thebody to respond to the previous change in therapy.

Diagnosis and Treatment

One of skill in the art will understand that the system described abovein relation to FIGS. 4-5B may also be applicable to a wide range oftissue phenomena and a wide range of treatment responses. For example,in certain embodiments, instead of providing an alert upon detection ofpoor blood flow, the controller may be configured to communicate with aNPWT device, such as described above in relation to FIGS. 1-2C. Such asystem may provide NPWT to a wound site when the controller indicatesthat treatment is merited.

One of skill in the art will further understand that the embodimentsinvolving EVM described above in relation to FIGS. 4-5B lend themselveswell to diagnosing the condition of intact tissue or the condition of awound. FIG. 6 illustrates an embodiment of a method 1300 for evaluatinga wound using EVM in combination with evaluation algorithms. The method1300 can be performed by a sensor and a controller. In 1302, video iscollected from a tissue site via any of the means described herein thissection or elsewhere in the specification, and using any sensordescribed herein this section or elsewhere in the specification. Such asensor may be positioned on a smartphone. However, in certainembodiments, the smartphone may be a tablet or other suitable computingdevice such as disclosed herein this section or elsewhere in thespecification. Nevertheless, for the purposes of explaining theembodiment of the method of FIG. 6 , the term “smartphone” will be used.

The video 1302 may be collected of any tissue site of interest, forexample a tissue site suspected of possible injury undetectable by thenaked eye or a tissue site that is being considered for possibletreatments such as NPWT. Once the video has been collected or as it iscollected in real-time, EVM may be applied to the video according to themethods described herein this section or elsewhere in the specification1304. Once EVM has been applied, a processor or controller containedwithin the smartphone may analyse 1306 the image to calculate deltavalues (change values) for certain pixels and/or regions, similar to themethods described above in relation to FIGS. 5A-5B. Once the deltavalues have been calculated, the processor may overlay the delta valueson top of the video or a static image to display an overlain image to acaregiver. Such an overlay may be displayed by any suitable, such asdisclosed herein this section or elsewhere in the specification, forexample, a smartphone screen. In certain embodiments, an algorithm maybe used to cross-reference particular features with a database of tissuetypes and phenomena. Therefore, the overlay may include information suchas identifying a blood vessel, a wound, a subcutaneous injury, ahematoma, an oedema, or any other suitable tissue or phenomena.

In further examples, for deep tissue injury diagnoses, a clinicianand/or the algorithm may identify a region of tissue for application ofoffloading. Further treatments to the identified tissue may be to applya dressing such as Allevyn Life by Smith & Nephew. Further treatmentscould include a recommendation for application of massage and/orskincare products to the site. In certain embodiments, NPWT may bemerited to an unbroken tissue site, such as disclosed earlier in thespecification; for example, a Pico device by Smith & Nephew may beapplied.

The overlay 1306 may provide treatment information 1308 to theclinician. For example, if the delta value(s) in a particular area ofthe wound or tissue site are/is low, as described above in relation toFIGS. 4-5B, this may indicate poor blood flow to a particular area. Suchan analysis may indicate to the physician that a treatment 1310, such asNPWT is merited to treat such tissue. In some embodiments, thesmartphone may be configured to directly communicate with a NPWT deviceto start treatment, either automatically or via manual prompt.Alternatively, if the delta is low but the overall color value ishigher, this may indicate the presence of a contusion. Alternativemeaning for a low delta could be the presence of oedema. In certainembodiments, for oedema NPWT and/or compressing may be recommended. Inthe case of possible ulcers, such as a diabetic ulcer, then off-loadingby removing pressure may be recommended.

For identification of necrotic tissue, such tissue may be treatedthrough the use of waterjet debridement (e.g. Versajet by Smith &Nephew), plasma debriders, and/or enzymatic debriders, such ascollagenase. Necrotic tissue may also be debrided using more traditionaltechniques such as mechanical cutting or abrading devices. In thescenarios of monitoring venous leg ulcers, for example, an area whereminimal change in blood or very low oxygenated blood is identified, thismay show a blocked vein and/or a perforated vein. In such cases surgicalintervention for removal of the vein or blockage may be recommended.Advantageously, such a diagnosis may improve upon current methods usingultrasound (from behind the wound, to avoid contamination).

One of skill in the art will understand that all of the treatmentmethods described herein this section or elsewhere in the specification,may be autonomous such that a treatment device may communicate with thecomputing device and be instructed directly to apply treatment withouthuman intervention. Such treatment could combine multiple therapies,such as NPWT and debridement, as merited by the analysis of the tissuevia EVM or other suitable means.

In certain embodiments, further information may be collected around theedges of a wound. For example, the smartphone may identify the edge ofthe wound by identifying that skin colour in that particular location ischanging by less than the wound area during a pulse or physical movementreduced on healed skin. Such an approach may work in concert with asemi-static colour measurement to augment the identification of skin vs.wound colouration. In some embodiments, the data may be transmitted fromthe dressing either to the wearer's phone, to a nursescommunication-enabled device, to a data hub, to an indication station,or to any suitable system or device. A negative trajectory may behighlighted to perform an intervention and upgrade the treatment path. Apositive healing pathway may identify that the current treatment issuccessful and can be continued or even downgraded to a cheaper and/orless aggressive treatment.

Returning to potential analysis of a tissue site, as described elsewheredamaged tissue may not have much blood flow and may therefore have a lowdelta value. However, as the tissue heals, the area showing a tissueparameter/delta value of healthy tissue should increase. If the healthyarea is increasing quickly then there may be no requirement to utilizefurther aggressive and expensive treatments as the body is healing onits own. If the area that is healthy is not increasing then a greaterintervention may be required (e.g. the raise to a more expensivepathway, for example, changing from a passive dressing to NPWT oranother therapy such as antimicrobials).

If certain tissue regions have a delta close to zero, than this mayindicate that the tissue is necrotic. In such instances, the smartphonealgorithm may recommend removal of such tissue via debridement, such asvia plasma debrider, water debrider, or enzymatic debrider. In someembodiments, the smartphone could be configured to communicate directlywith a plasma or water debrider and apply debridement to the wound siteuntil the zero delta tissue is removed and only healthy tissue remainsand is identified with a positive delta.

In certain embodiments, the smartphone sensor may be used to identifythe presence of blood vessels that may not be apparent to the naked eye.Such detection may be valuable for guiding a clinician in theapplication of NPWT because application of NPWT directly to a bloodvessel can be dangerous. Areas with blood vessels close to the surfacewill likely result in a high delta value due to the change in color orother parameter (such as motion) between blood pulses. However, to avoidfalse positives from very small capillaries, it may be necessary tomodify the region selection such that a number of pixels are selected,otherwise a single pixel could show a very high delta value, but onlydue to a single capillary. In certain embodiments, the smartphone couldcontain algorithms to detect the present of exudate over the top of thewound, thereby guiding a physician toward the removal of such exudate.

Returning to FIG. 6 , in certain embodiments, video collection 1302could occur between wound dressing changes. Conventional dressings maybe changed a few times a day, once a day, a few times a week, once aweek, or less often than once a week. Once video of the wound betweendressing applications is collected, EVM could be applied, providingenhanced information about the state of the wound between dressingchanges. Comparison between video taken at different time points betweendressing changes may provide a caregiver with enhanced informationregarding the state of the wound, such as by analysing the image andapplying an overlay 1306. The smartphone may be configured with analgorithm to provide a treatment recommendation to the clinician,depending on the changing characteristics of the healing wound, such asthe amount of wound closure or the present of undesirable tissue types

In some embodiments, for a size comparison of a wound between dressingchanges, a fixed-size 2D barcode (or other fixed image) may be used toidentify the size baseline (and orientation). In particular embodiments,a colour-based algorithm may be used to identify common features betweenthe wound at different times in order to scale the image. A first imagefrom an earlier treatment time may be ghosted over a new image to allowthe caregiver to align and scale the wound images in time. In certainembodiments, multiple cameras may be used to identify the size and/orthe camera rangefinder may be used to identify the size and re-scale.

Embodiments Using Additional Signal Inputs

Magnetic Induction Tomography

In some embodiments, the systems and methods described above in relationto FIGS. 4-6 may be used with different types of signals such as thesignal provided from magnetic induction tomography (MIT). In someembodiments, with the multiple-coil options, one coil may be pulsed at ahigh repeat rate (for example in the range 5 to 25 ‘frames’ per second)to capture “frames” to identify the underlying heart rate. The rest ofthe coils may then be used at a rate closer to that heart rate which mayallow the “shutter speed” to be reduced (e.g. to closer to 2 to 5‘frames’ per second) leading to a longer exposure without as much noisefrom the heart rate on the signal. In some embodiments, tissue damagesuch as pressure insult may then be identified through either or both ofa “static” signal where little delta change is observed at the pulsefrequency and/or in a Eulerian amplified signal with changes betweenamplified frames. In certain embodiments utilizing multiple coils, whereeach coil can interfere with the next, the difference between the coilsat the heart frequency could be used to remove the noise due to thepresence of the other coils. For example, bruising or other damage inthe tissue may be identified as a location at which the heart-rate pulsedoes not change the tissue inductance between peak and lowest pulsepressure. This information may be used to supplement the “static”identification of whether there is blood (which could be healthy tissue,a bruise or a clot) or an absence of blood (ischemia), thereforeallowing separation of the different states with blood present.

In certain embodiments, the output may be an EVM video identifying thechange in inductance (with different colours representing differentinductances), a numerical value, or a diagnosed value identifying thepresence of a volume to which blood is not going (ischemia) or which isdamaged (bruise/clot) and triggering an alert from a alerting elementsuch as disclosed herein this section or elsewhere in the specification.

Ultrasound

In certain embodiments, and as described above in relation to thedisclosed sensors, Eulerian Video Magnification may also be applied toultrasound video of a tissue site 1302. In some embodiments, tissuedamage such as pressure insult may then be identified through either orboth of a “static” signal where little delta change is observed at thepulse frequency and/or in a Eulerian amplified signal with changesbetween amplified frames. As with magnetic induction tomographydescribed above, bruising or other damage in the tissue may beidentified as a location at which the heart-rate pulse does not changethe tissue noise response between peak and lowest pulse pressure. Thisinformation may be used in addition to the “static” identification ofwhether there is blood (which could be healthy tissue, a bruise or aclot) or an absence of blood (ischemia), therefore allowing separationof the different states with blood present.

In certain embodiments, the output may be an EVM video identifying thechange in inductance (with different colours representing differentinductances), a numerical value, or a diagnosed value identifying thepresence of a volume to which blood is not going (ischemia) or which isdamaged (bruise/clot) and triggering an alert from a alerting elementsuch as disclosed herein this section or elsewhere in the specification.

Temperature Signals

In certain embodiments, the systems and methods described above inrelation to FIGS. 4-6 may be applied to temperature signals. As withmagnetic induction tomography and ultrasound, bruising or other damagein the tissue may be identified as a location at which the heart-ratepulse does not change the tissue noise response between peak and lowestpulse pressure. This information may be used in addition to the “static”identification of whether there is blood (which could be healthy tissue,a bruise or a clot) or an absence of blood (ischemia), thereforeallowing separation of the different states with blood present.

In certain embodiments, the output may be an EVM video identifying thechange in inductance (with different colours representing differentinductances), a numerical value, or a diagnosed value identifying thepresence of a volume to which blood is not going (ischemia) or which isdamaged (bruise/clot) and triggering an alert from a alerting elementsuch as disclosed herein this section or elsewhere in the specification.

In some embodiments, thermistors or thermocouples could be used in placeof the RGB sensor/CCD and light sources described above in relation toFIGS. 4-6 . A grid or matrix of such sensors may be mountedclose-coupled to the tissue. These sensors may then be used in concertwith other sensors (e.g. optical or EEG/ECG) to allow separation of theheart rate from the temperature noise of the environment (i.e.identifying the temperature changes that occur at the frequency of theheart pulse). In certain embodiments, infrared measurements, such asdisclosed herein this section or elsewhere the specification may be usedfor temperature measurements.

Electromagnetic Generator

In certain embodiments, one or more electromagnetic (EM) generators andreceivers may be mounted in an object such as a bed or chair, pointingupwards, similar to the embodiments described above in relation to FIG.4 . In some embodiments, the materials of the mattress and bedding maybe transparent to the EM frequency (e.g. millimetre wave). The sourceand sensor may also be remote with an EM guide such as an optical fibredirecting the waves to the correct location and direction. In someembodiments, the emission location may be either beneath themattress/padding or at some point closer to the occupant, but may besuitably padded to minimise point loading, risking pressure injury. In abed implementation, the source may shine through the bed/bedding and bereflected off the tissue of the occupant of the bed. The EM wave maythen be collected at the receiver and EVM performed on this returnedwave. The output of the amplification, as processed by an algorithmindicating a need for intervention, may be sent to either abed/chair-mount indicator with an alarm element such as disclosed hereinthis section or elsewhere in the specification or communicated to anexternal alarm element by a wired or wireless connection. If the patientis incontinent, urine and other waste will also reflect the millimetrewave signal and may be indicated as an event. Incontinence is acontributing factor to tissue breakdown through maceration, thereforeidentification and quick intervention may improve outcomes.

Langer's Lines

In some embodiments, the systems and methods described above in relationto FIGS. 4-6 may be used to identify and utilize Langer's lines as asurgical guide for forming incisional wounds. Langer's lines aretopological lines drawn on a map of the human body corresponding to thenatural orientation of collagen fibers in the dermis, generally parallelto the orientation of the underlying muscle fibers. Knowledge of thedirection of Langer's lines within a specific area of the skin can beimportant for surgical operations, particularly cosmetic surgery. Whenpossible, a surgeon will preferably cut in the direction of Langer'sLines within a given tissue site. Surgical incisions made parallel toLanger's lines tend to heal more quickly and produce less scarringcompared to surgical incisions that cut across Langer's Lines. Incisionsmade perpendicular to Langer's lines have a tendency to pucker andremain obvious to the naked eye, although sometimes this is unavoidabledepending on the required surgical intervention. For example, theorientation of stab wounds relative to Langer's lines can have aconsiderable impact upon the presentation of the wound. Further, keloidsare more common for incisions across Langer's Lines. General maps ofLanger's Lines are available to give a surgeon a general understandingof the position and orientation of Langer's Lines across the entirehuman body, however, such maps are not perfectly accurate and do notcapture the particular Langer's Line orientations within every patientdue to variation across populations and individuals. In some cases, useof a real-time image enhancement technology, such as the EVM embodimentsdescribed above in relation to FIGS. 4-6 , may be advantageous toprovide a surgeon with proper guidance regarding incision site.

FIG. 7 illustrates an embodiment of a method and/or system 1400 forevaluating a potential incision site using EVM in combination withevaluation algorithms that identify Langer's Lines. The method and/orsystem 1400 can include and/or be implanted by a sensor and acontroller. In 1402, video is collected from a tissue site via any ofthe means described herein this section or elsewhere in thespecification, and using any sensor described herein this section orelsewhere in the specification. Such a sensor may be positioned on asmartphone. However, in certain embodiments, the smartphone may be atablet or other suitable computing device such as disclosed herein thissection or elsewhere in the specification. Nevertheless, for thepurposes of explaining the embodiments of FIG. 7 , the term “smartphone”will be used.

The video 1402 may be collected of any tissue site of interest, forexample a tissue site suspected of possible injury undetectable by thenaked eye or an obviously wounded tissue site. In some embodiments, thevideo may be collected of a tissue site identified as a potentialsurgical site, requiring access to an internal tissue site throughsurgical incision. As described above, Langer's Lines are used bysurgeons to identify surgical incision sites.

Once the video has been collected or as it is collected in real-time,EVM may be applied to the video according to the methods describedherein this section or elsewhere in the specification 1404. Once EVM hasbeen applied, a processor or controller contained within the smartphonemay analyse 1406 the video image to identify Langer's Lines within thetissue site by calculating delta values (change values) for certainpixels and/or regions, similar to the methods described above inrelation to FIGS. 4-6 . For example, the processor or controller mayidentify areas of skin tension based on amplified video data of statictissue or tissue undergoing movement. Areas of skin tension may be usedto identify Langer's Lines. In some embodiments, Blaschko's Lines and/orKraissl's lines may also be identified by amplifying video of static ormoving skin. In certain embodiments, skin may be pinched or otherwisemanipulated to create wrinkles in the skin, corresponding to Langer'sLines. In certain embodiments, EVM may amplify video of skin such thatdifferent tissues are identified, such as collagen bundles within theskin. The processor or controller may utilize these collagen bundles tomap and identify Langer's Lines.

Once the delta values have been calculated, the processor may overlaythe delta values on top of the video or a static image to display anoverlain image to a caregiver. Such an overlay may be displayed by anysuitable display, such as disclosed herein this section or elsewhere inthe specification, for example, a smartphone screen. In certainembodiments, an algorithm may be used to cross-reference particularfeatures with a database of tissue types and phenomena. Similar to theabove embodiments as disclosed in relation to FIGS. 4-6 , the overlaymay include information such as identifying a blood vessel, a wound, asubcutaneous injury, a hematoma, an oedema, or any other suitable tissueor phenomena. Alternatively or in combination with the above, theprocessor may overlay Langer's Lines based on database informationregarding the most common positions and orientations of Langer's Linesin the human body.

In certain embodiments, the overlay may include Langer's Lines appliedover the image or video of the tissue site in a topographical map. Suchan overlay may include solid lines to indicate the positions of theLanger's Lines and/or arrows to identify the direction and orientationof the Langer's Lines. The Langer's Lines may then be utilized by asurgeon to identify the proper orientation and location of a potentialincision site 1408. Once an incision site has been identified, thesurgeon may make an incision 1410 while video continues to be collectedand amplified. Therefore, the surgeon may monitor minute changes in thetissue site, during surgery.

In some embodiments, an alert may be generated when a particularthreshold and/or parameter relating to Langer's Lines is reached. Forexample, a controller, such as any controller disclosed herein thissection or elsewhere in the specification, may provide an alert to thecaregiver to notify the surgeon that a particular incision is notaligned with the Langer's Lines. Such an alert may be provided via anymeans disclosed herein this section or elsewhere in the specification.Further alerts may be provided when other thresholds and/or parametersare reached, such as any of the thresholds and/or parameters disclosedherein this section or elsewhere in the specification.

Magnetic Induction Tomography with Ultrasound

As described above, ultrasound may be used to image a tissue site.However, ultrasound may also be used therapeutically to acceleratehealing. In some embodiments, therapeutic ultrasound may be applied at afrequency of between about: 0.5-10 MHz, such as about 1-5.0 MHz, orabout 1 to 3.0 MHz. Such healing therapy may be performed on internaltissue sites, such as a ligament in the shoulder, knee, or othersuitable location. However, although therapeutic ultrasound may bedelivered to an internal tissue site, the progress of said healing ofthe internal tissue site is typically difficult to monitor. For example,conventional imaging means may not be able to detect minute changes inthe tissue, thereby making it difficult to determine whether acceleratedhealing is occurring. Further, conventional imaging means may not beable to monitor delivery of the ultrasound in real-time, thereby makingit difficult for a clinician to understand the efficacy of theultrasound treatment.

FIG. 8 illustrates an embodiment of a treatment system 1500 thatutilizes therapeutic ultrasound delivery from an ultrasound device 1502to an internal tissue site 1504 in combination with monitoring viamagnetic induction tomography (MIT) 1506, described above. One of skillin the art will understand that such a tissue site may encompass anysuitable tissue site, such as the ligaments of the shoulder, knee,elbow, or other suitable joint. One of skill in the art will furtherunderstand that the methods and devices described in relation to FIGS.4-7 above may also be suitable for the embodiment of FIG. 8 .

In some embodiments, during delivery of therapeutic ultrasound, an MITdevice 1506, such as described herein this section or elsewhere in thespecification and applied such as described herein this section orelsewhere in the specification, may collect magnetic induction imagingdata of the internal tissue site before, during, or after delivery oftherapeutic ultrasound. As described above, MIT advantageously allowsfor deep tissue data and image collection. Such imaging data may then betransmitted to a controller or processor 1508 (hereinafter“controller”), the controller configured to amplify the image data usingEVM according to any suitable methods described herein this section orelsewhere in the specification. The controller may then transmit theamplified image to a display 1510 to display the image, in real-time,before, or after delivery of therapeutic ultrasound. In someembodiments, the controller may transmit the image in unamplified form,simply conveying the MIT image and associated data such as disclosedherein this section or elsewhere in the specification.

In some embodiments, the controller 1508 may be configured to analysethe amplified image such as via any suitable method disclosed hereinthis section or elsewhere in the specification such as in FIGS. 4-7 , todetect minute changes in the image. For example, as described above, thecontroller may detect minute changes in movement or color of theinternal tissue. Such information on the minute changes in the amplifiedimage may provide information regarding the effectiveness of thetherapeutic ultrasound. Therefore, the controller may be configured touse the amplified pixel data to detectstrengthening/healing/reattachment of the damaged tissue, such as bydetecting a minute increase in density of certain soft and/or hardtissues that comprise the tissues of a mammalian joint. Further, thecontroller may be configured to use the amplified pixel data to identifychanges in perfusion, increases in blood or other fluid flow to thedamaged tissue and/or the migration of certain cells to the damagedtissue. Such detecting of minute changes in the healing of the tissuemay be used to calculate a healing factor, which indicates theeffectiveness of the therapeutic ultrasound induced healing.

In some embodiments, the controller 1508 may be configured to provide analert, such as any alert described herein this section or elsewhere inthe specification when the healing factor exceeds or falls below athreshold indicative of healing. This alert may be used by a caregiverto adjust the therapeutic ultrasound. In some embodiments, the alert mayindicate the need to specifically adjust the therapeutic ultrasound suchas by altering the frequency, amplitude, or general pulse frequency suchas to intermittent or continuous. The threshold may be set by acaregiver or provided automatically based on previous patientinformation or by values found in the literature. In some embodiments,upon exceeding or falling below a threshold level for a healing factor,the controller may communicate with the ultrasound delivery device toautomatically alter the parameters of the ultrasound delivery such as byraising or lowering the frequency or amplitude, and/or by altering apulse/continuous delivery pattern of ultrasound.

In certain embodiments, the ultrasound delivery device and MIT devicemay be configured to coordinate via the controller. For example, thecontroller may be configured to only collect MIT image data while theultrasound delivery device is operating. In some embodiments, thecontroller may alter the direction, timing or other parameters of theMIT device in response to changes in the therapeutic ultrasound.

In some embodiments, the computing systems described herein may includeone or more computing devices, for example, a server, a laptop computer,a mobile device (for example, smart phone, smart watch, tablet, personaldigital assistant), a kiosk, automobile console, or a media player, forexample. In some embodiments, the computing devices may include one ormore central processing units (CPUs), which may each include aconventional or proprietary microprocessor. Computing devices mayfurther includes one or more memory, such as random access memory (RAM)for temporary storage of information, one or more read only memory (ROM)for permanent storage of information, and one or more mass storagedevices, such as a hard drive, diskette, solid state drive, or opticalmedia storage device. In certain embodiments, the processing device,cloud server, server or gateway device, may be implemented as acomputing system. In one embodiment, the modules of the computingsystems are connected to the computer using a standard based bus system.In different embodiments, the standard based bus system could beimplemented in Peripheral Component Interconnect (PCI), Microchannel,Small Computer computing system Interface (SCSI), Industrial StandardArchitecture (ISA) and Extended ISA (EISA) architectures, for example.In addition, the functionality provided for in the components andmodules of the computing devices disclosed herein may be combined intofewer components and modules or further separated into additionalcomponents and modules.

The computing devices disclosed herein may be controlled and coordinatedby operating system software, for example, iOS, Windows XP, WindowsVista, Windows 7, Windows 8, Windows 10, Windows Server, EmbeddedWindows, Unix, Linux, Ubuntu Linux, SunOS, Solaris, Blackberry OS,Android, raspberry Pi, Arduino, or other operating systems. In Macintoshsystems, the operating system may be any available operating system,such as MAC OS X. In other embodiments, the computing device may becontrolled by a proprietary operating system. Conventional operatingsystems control and schedule computer processes for execution, performmemory management, provide file system, networking, I/O services, andprovide a user interface, such as a graphical user interface (GUI),among other things.

The computing devices disclosed herein may include one or more I/Ointerfaces and devices, for example, a touchpad or touchscreen, butcould also include a keyboard, mouse, and printer. In one embodiment,the I/O interfaces and devices include one or more display devices (suchas a touchscreen or monitor) that allow visual presentation of data to auser. More particularly, a display device may provide for thepresentation of GUIs, application software data, and multimediapresentations, for example. The computing systems disclosed herein mayalso include one or more multimedia devices, such as cameras, speakers,video cards, graphics accelerators, and microphones, for example.

In general, the word “module,” as used herein, refers to logic embodiedin hardware or firmware, or to a collection of software instructions,possibly having entry and exit points, written in a programminglanguage, such as, for example, Python, Java, Lua, C and/or C++. Asoftware module may be compiled and linked into an executable program,installed in a dynamic link library, or may be written in an interpretedprogramming language such as, for example, BASIC, Perl, or Python. Itwill be appreciated that software modules may be callable from othermodules or from themselves, and/or may be invoked in response todetected events or interrupts. Software modules configured for executionon computing devices may be provided on a computer readable medium, suchas a compact disc, digital video disc, flash drive, or any othertangible medium. Such software code may be stored, partially or fully,on a memory device of the executing computing device, for execution bythe computing device. Software instructions may be embedded in firmware,such as an EPROM. It will be further appreciated that hardware modulesmay be comprised of connected logic units, such as gates and flip-flops,and/or may be comprised of programmable units, such as programmable gatearrays or processors. The block diagrams disclosed herein may beimplemented as modules. The modules described herein may be implementedas software modules, but may be represented in hardware or firmware.Generally, the modules described herein refer to logical modules thatmay be combined with other modules or divided into sub-modules despitetheir physical organization or storage.

Each of the processes, methods, and algorithms described in thepreceding sections may be embodied in, and fully or partially automatedby, code modules executed by one or more computer systems or computerprocessors comprising computer hardware. The code modules may be storedon any type of non-transitory computer-readable medium or computerstorage device, such as hard drives, solid state memory, optical disc,and/or the like. The systems and modules may also be transmitted asgenerated data signals (for example, as part of a carrier wave or otheranalog or digital propagated signal) on a variety of computer-readabletransmission mediums, including wireless-based and wired/cable-basedmediums, and may take a variety of forms (for example, as part of asingle or multiplexed analog signal, or as multiple discrete digitalpackets or frames). The processes and algorithms may be implementedpartially or wholly in application-specific circuitry. The results ofthe disclosed processes and process steps may be stored, persistently orotherwise, in any type of non-transitory computer storage such as, forexample, volatile or non-volatile storage.

All of the features disclosed in this specification (including anyaccompanying exhibits, claims, abstract and drawings), and/or all of thesteps of any method or process so disclosed, may be combined in anycombination, except combinations where at least some of such featuresand/or steps are mutually exclusive. The disclosure is not restricted tothe details of any foregoing embodiments. The disclosure extends to anynovel one, or any novel combination, of the features disclosed in thisspecification (including any accompanying claims, abstract anddrawings), or to any novel one, or any novel combination, of the stepsof any method or process so disclosed.

Various modifications to the implementations described in thisdisclosure may be readily apparent to those skilled in the art, and thegeneric principles defined herein may be applied to otherimplementations without departing from the spirit or scope of thisdisclosure. Thus, the disclosure is not intended to be limited to theimplementations shown herein, but is to be accorded the widest scopeconsistent with the principles and features disclosed herein. Certainembodiments of the disclosure are encompassed in the claim set listedbelow or presented in the future.

What is claimed is:
 1. A treatment system, comprising: a visualization sensor configured to be positioned over a tissue site, the visualization sensor configured to collect magnetic induction tomography video data of the tissue site; an output configured to provide a first alert; and a controller in communication with both the visualization sensor and the output, the controller configured to: amplify the video data by Eulerian video magnification; determine a treatment parameter from the amplified video data, wherein the treatment parameter is derived from a red-delta value and changes in pulse motion indicative of blood flow to the tissue site; cause the output to provide the first alert in response to determining that the treatment parameter differs from a threshold; identify areas of skin tension in the tissue site from the amplified video data; identify Langer's Lines in the tissue site from the identified areas of skin tension; and identify an intended incision site and wherein the controller is configured to provide a second alert in response to determining that an intended incision site is not aligned with the Langer's Lines.
 2. The treatment system of claim 1, wherein the threshold corresponds to a probability of occurrence of a pressure injury.
 3. The treatment system of claim 1, wherein the controller is contained within a smartphone.
 4. The treatment system of claim 1, wherein the visualization sensor is configured to communicate wirelessly with the controller.
 5. The treatment system of claim 1, wherein the controller is configured to communicate wirelessly with the output.
 6. The treatment system of claim 1, wherein the controller is configured to compare the treatment parameter to a plurality of thresholds.
 7. The treatment system of claim 1, wherein the visualization sensor comprises an RGB detector.
 8. The treatment system of claim 1, wherein the first or second alerts comprise an audible alarm.
 9. The treatment system of claim 1, wherein the first or second alerts comprise a visual alarm.
 10. The treatment system of claim 1, wherein the controller is configured to determine a tissue parameter by calculating the change in a red value between two or more frames of the video data.
 11. The treatment system of claim 1, wherein the controller is configured to provide the first alert when the magnetic induction tomography video data exceeds a threshold.
 12. A method of operating a treatment system comprising a visualization sensor and a controller, the method comprising: by the visualization sensor positioned over a tissue site, collecting video data of the tissue site; and by the controller: amplifying the video data by Eulerian video magnification; determining a treatment parameter from the amplified video data, wherein the treatment parameter is derived from a red-delta value and changes in pulse motion indicative of blood flow to the tissue site; causing provision of an alert in response to determining that the treatment parameter differs from a threshold; identifying areas of skin tension in the tissue site from the amplified video data; identifying Langer's Lines in the tissue site from the identified areas of skin tension; and identifying an intended incision site and providing an incision site alert in response to determining that an intended incision site is not aligned with the Langer's Lines, the incision site alert comprising an orientation and a position.
 13. The method of claim 12, further comprising the controller mapping the Langer's Lines over the video data and displaying the Langer's Lines on a display.
 14. A treatment system, comprising: a visualization sensor configured to be positioned over a tissue site, the visualization sensor configured to collect video data of the tissue site; an output configured to provide a first alert; and a controller in communication with both the visualization sensor and the output, the controller configured to: amplify the video data by Eulerian video magnification; determine a treatment parameter from the amplified video data, wherein the treatment parameter is derived from a red-delta value and changes in pulse motion indicative of blood flow to the tissue site; cause the output to provide the first alert in response to determining that the treatment parameter differs from a threshold; identify areas of skin tension in the tissue site from the amplified video data; identify Langer's Lines in the tissue site from the identified areas of skin tension; identify an intended incision site and wherein the controller is configured to provide a second alert in response to determining that an intended incision site is not aligned with the Langer's Lines; and map the Langer's Lines over the video data and display the Langer's Lines on a display. 